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The correct ANSWER is (a) single-headed empty arrow

To explain: The UML describes the INHERITANCE relationship as a generalization. This relationship is signified by a line leading from the subclass to its PARENT. The line is TIPPED with an empty closed arrow.

Right answer is (a) OPERATIONS

Best EXPLANATION: Operations describe methods, or more properly, they describe the CALLS that can be MADE on an instance of a class.

Correct OPTION is (C) Protected

Easy EXPLANATION: Available to the CURRENT CLASS and its subclasses only.

The CORRECT CHOICE is (a) double-headed arrow

Best EXPLANATION: A UNIDIRECTIONAL ASSOCIATION has single-headed arrow.

Right option is (c) AGGREGATION

Easy EXPLANATION: In the CASE of aggregation, the contained objects are a core PART of the container, but they can also be contained by other objects at the same TIME.

The correct OPTION is (a) Public

To ELABORATE: The visibility symbol is FOLLOWED by the NAME of the attribute.

The CORRECT ANSWER is (c) Attributes

For explanation I would say: Attributes describe a class’s properties. Attributes are listed in the section DIRECTLY beneath the class name.

Correct CHOICE is (b) Constraints

The best explanation: The {abstract} syntax is an example of a constraint. There is no SPECIAL structure for the text between the braces; it should simply provide a short clarification of any conditions that may apply to the ELEMENT.

The correct choice is (c) Class NAME

To ELABORATE: The other two SECTIONS are OPTIONAL when no more information than the class name is known.

Correct answer is (d) unified modeling language

For explanation: The UML EMERGED as a standard only after long years of intellectual and BUREAUCRATIC SPARRING among the great and good of the OBJECT oriented design community.

Right CHOICE is (d) class switching

The explanation: POLYMORPHISM is the MAINTENANCE of multiple implementations behind a COMMON INTERFACE.

Right option is (b) TIGHT Coupling

Explanation: Tight coupling is by no means UNIQUE to PROCEDURAL code, THOUGH the sequential nature of such code makes it prone to the problem.

The correct option is (a) Orthogonal

The EXPLANATION: Orthogonality, it is argued, promotes reuse in that components can be plugged into new systems without needing any SPECIAL CONFIGURATION. Such components will have clear inputs and outputs independent of any wider CONTEXT.

The CORRECT answer is (C) Cohesion

Best explanation: Ideally, you should create components that share a clear responsibility. If your code spreads RELATED routines widely, you will find them harder to maintain as you have to hunt around to make changes. Our PARAM Handler classes collect related PROCEDURES into a common context.

Right option is (b) CLIENT code

Best EXPLANATION: Procedural code takes the form of a sequential series of commands and method calls. The controlling code TENDS to take responsibility for handling differing conditions. This top-down control can result in the development of duplications and dependencies across a project. Object-oriented code tries to minimize these dependencies by moving responsibility for handling tasks away from client code and TOWARD the objects in the system.

Correct ANSWER is (a) CHILD parent

Explanation: Such a design decision does have its own consequences, HOWEVER.

The correct option is (a) class_implements()

For explanation: is_subclass_of() will tell you only about CLASS inheritance RELATIONSHIPS. It will not tell you that a class IMPLEMENTS an interface.

Right answer is (a) get_parent_class()

Easiest EXPLANATION: The class functions also allow US to chart INHERITANCE relationships.This function requires either an object or a class name, and it returns the name of the superclass, if any. If no such class exists, that is, if the class we are testing does not have a parent, then the function returns FALSE.

The correct choice is (d) True

Easiest explanation: method_exists() RETURNS true for PRIVATE and protected methods as well as for PUBLIC ones. Remember that the fact that a METHOD EXISTS does not mean that it will be callable.

Right ANSWER is (C) is_callable()

The explanation is: There is another method which you can USE – method_exists() for SIMILAR purpose.

Right ANSWER is (C) is_a()

To elaborate: As of PHP 5.3 is_a() no LONGER DEPRECATED.

The correct option is (d) get_class()

EASIEST explanation: This function ACCEPTS any OBJECT as an argument and returns its CLASS name as a string.

Right choice is (b) class_exists()

To elaborate: The class_exists() function accepts a string representing the class to CHECK for and RETURNS a Boolean true VALUE if the class exists and false OTHERWISE.

The correct option is (a) once

Easiest EXPLANATION: __autoload is a powerful tool, but it does have some limitations. In particular, you can only define it once in a process. If you NEED to change your AUTOLOAD function DYNAMICALLY you should look at the spl_autoload_register function, which supports that FUNCTIONALITY.

Correct choice is (c) __autoload()

Best explanation: When the PHP engine encounters an attempt to instantiate an unknown class, it invokes the __autoload() function, passing it the class name as a string. It is up to the IMPLEMENTER to define a strategy for locating and including the MISSING class file.

Right choice is (d) Both do not handle the errors in the same way

For EXPLANATION I WOULD say: The only difference between the INCLUDE() and require() statements lies in their handling of errors. A file invoked using require() will bring down your entire process when you MEET an error. The same error ENCOUNTERED via a call to include() will merely generate a warning and end execution of the included file.

Correct answer is (a) namespace my;

EXPLANATION: The namespace declaration MUST be the FIRST statement in its FILE.

Right choice is (b) Classes

For explanation: A PACKAGE is a set of related classes, usually grouped together in some way. PACKAGES can be USED to SEPARATE PARTS of a system from one another.