Answer» Correct Answer - Option 3 : Conjunction
 The correct answer is : Conjunction  - In the given sentence "when" is connecting two clauses. 
 - In grammar a word which connects two words, two clauses and two sentences is called conjunction
 
   | part of speech | function or "job" | example words | example sentences | 
|---|
 | Verb |  describes action or state  | (to) be, have, do, like, work, sing, can, must | English Club is a web site. I like EnglishClub. |  | Noun | name of any person, place and thing | pen, dog, work, music, town, London, teacher, John | This is my dog. He lives in my house. We live in London. |  | Adjective | describes a noun | good, big, red, well, interesting | My dogs are big. I like big dogs. |  | Determiner | limits or "determines" a noun | a/an, the, 2, some, many | I have two dogs and some rabbits. |  | Adverb | describes a verb, adjective or adverb | quickly, silently, well, badly, very, really | My dog eats quickly. When he is very hungry, he eats really quickly. |  | Pronoun | replaces a noun | I, you, he, she, some | Tara is Indian. She is beautiful. |  | Preposition | links a noun to another word | to, at, after, on, but | We went to school on Monday. |  | Conjunction | joins clauses or sentences or words | and, but, when | I like dogs and I like cats. I like cats and dogs. I like dogs but I don't like cats. |  | Interjection | short exclamation, sometimes inserted into a sentence | oh!, ouch!, hi!, well | Ouch! That hurts! Hi! How are you? Well, I don't know. |  
 The correct answer is Conjunction 
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