[The same passage from Q.41 applies here]
Select the most appropriate synonym of the word epidemic stated in para 2 of the given passage.

The word epidemic in paragraph 2 ("loneliness and social isolation have reached epidemic proportions") refers to a widespread occurrence of an unwanted condition or disease.
Ailment means an illness or disease (typically a minor one), which fits closely in the context of health conditions spreading extensively.

Slump: A sudden severe economic or performance decline.

Calm: A state of tranquility.

Doldrums: A state of inactivity or stagnation.