Find the synonym of the underlined word.
The collapse of the stock market last year signalled the beginning of the economic crisis .
a. Rise
b. Failure
c. Rebirth
d. Debt
e. Revival

Hint: Synonyms are words that are similar in meaning. They should be in the same language. Synonyms are compiled in a book called a thesaurus.

Complete answer:
We have been asked to find the synonym of the word collapse from the given sentence. Collapse means the breaking down of something. A building will collapse if there is an earthquake. In this case, we are talking about the collapse of the stock market. A synonym similar to breaking down but related to the stock market is option b, failure. Therefore, the answer is option b. Thus, the sentence means that when the stock market failed last year, it signalled the beginning of the economic crisis.
Option a is rise. This is completely wrong since it is an antonym of collapse. How can the rise of stock markets result in an economic crisis? Rise in stock markets results in economic development. Therefore, option a is wrong.
Option c, that is rebirth, means to be born again. In simpler terms, it means that something is starting afresh. It signifies a new beginning of something which used to exist but had died. As already explained, the rebirth or new beginning of stock markets does not lead to an economic crisis. Thus, it is the wrong answer.
Option d, is debt. When a person is in debt, he owes something to someone. The word debt is usually and mainly used when dealing with money. It is not appropriate to be used in the given sentence. It is not even grammatically correct in the context of the given sentence.
Option e, is revival which is synonymous to the word rise in option a. It is not a synonym of the given word collapse. Since it is a synonym of rise, it is an antonym of collapse. Therefore, it is the wrong answer.

Note: It is advised to have a good vocabulary to ace questions related to synonyms. Lists of synonyms are given in a thesaurus as well as on various sites on the internet. Students are; so advised to read books to have a good grasp over vocabulary.