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The correct ANSWER is (a) __call

Best explanation: When a class IMPLEMENTS __call(), then an object of that class is called with a method that doesn’t EXIST, __call() is called INSTEAD.

Right option is (d) Method chaining

To elaborate: When MANY METHODS are called in a single INSTRUCTION in PHP, it is called method chaining. FOLLOWING is a basic example of method chaining in php:

Correct answer is (a) INTERFACE

Easy explanation: An interface in PHP consists of METHODS that have no implementations, i.e. the interface methods are abstract methods. The methods in the interfaces must have public VISIBILITY scope. The interfaces are DIFFERENT from classes as the class can inherit from one class only whereas the class can IMPLEMENT one or more interfaces.

Right CHOICE is (b) __clone()

EASIEST EXPLANATION: A COPY of an OBJECT is created by using the clone keyword, which calls the object’s __clone() method.

Correct choice is (c) Abstract class

To explain: The abstract classes are the classes in which at least ONE method need to be abstract. Abstract classes in PHP are declared with the help of KEYWORD abstract. The use of class abstract are that all base classes implementing abstract class should give implementation of abstract methods declared in parent class.

Correct choice is (b) destinationObject = clone targetObject;

Easy EXPLANATION: You can clone an OBJECT by prefacing it with the clone KEYWORD. A copy of an object is created by using the clone keyword. $copy_of_object = clone $object;

The correct choice is (b) PHP 5

For explanation: ADVANCED concepts of OOP were introduced in PHP version 5.

The correct answer is (c) static

Explanation: Sometimes it is very handy to access the methods and properties in terms of a CLASS RATHER than an object. But this can be done through static keyword. Any method declared as ‘static’ can be ACCESSED WITHOUT the CREATION of an object.

Correct choice is (d) $this

Easy explanation: In PHP, the SELF and ‘this’ keyword are used to refer the class MEMBERS within the SCOPE of a class itself. The class members can be EITHER variables or functions.

The correct option is (a) extends

Explanation: When we EXTEND a CLASS then the subclass will INHERIT all the public and PROTECTED methods from the parent class.

The keyword IMPLEMENTS are used with interfaces. With inheritance, we use the keyword extends.

The correct OPTION is (c) is_a()

EASY explanation: The is_a() function returns true if object belongs to a class TYPE or if it belongs to a class that is a child of that class. Or else false is RETURNED.

The correct ANSWER is (C) Final

The BEST I can EXPLAIN: When we declare a method is as final then it is not possible to override that method. Methods should not be overridden DUE to some security or any other reasons.

Correct answer is (B) PHP 5

Explanation: Using instanceof keyword we can determine WHETHER an object is an instance of a CLASS. $manager = new Employee() … if ($manager instanceof Employee) ECHO “True”;

The correct OPTION is (d) function __construct()

Best explanation: A DOUBLE underscore FOLLOWED by the CONSTRUCT keyword. Its syntax is function __construct ([ argument1, argument2,…..]) { Class Initialization code }.

Correct choice is (a) $OBJECT->methodName();

The EXPLANATION is: “->” is a dynamic class METHOD INVOCATION in PHP.

Correct answer is (d) CONST PI = ‘3.1415’;

Explanation: Class CONSTANTS are created LIKE: const NAME = ‘VALUE’;

Correct answer is (c) $obj = NEW foo ();

BEST explanation: To create a new OBJECT in PHP we can USE the new statement to instantiate a CLASS.

Right option is (a) friendly

To explain: PHP supports FIVE class property SCOPES: PUBLIC, private, protected, final and STATIC.

Correct ANSWER is (d) class INSTANTIATION

To EXPLAIN: In object-oriented programming, classes are the blueprints of php OBJECTS. Classes do not actually become objects until instantiation is done. When someone instantiates a class, it creates an INSTANCE of it, thus creating the object. In other words, instantiation is the process of creating an instance of an object in memory.

Correct choice is (b) Polymorphism

For explanation I would say: The word polymorphism is DERIVED from Greek word poly which MEANS “many” and morphism which means the property which helps US to assign more than ONE property.

Correct CHOICE is (C) ENCAPSULATION

The best I can explain: In object-oriented PHP encapsulation is a CONCEPT of wrapping up or binding up the data MEMBERS and methods in a single module.