Based on the situation in the sentence, select the most appropriate idiom for the underlined segment.
After the Pandemic, his business crumbled and he is in a difficult situation.

The correct option is Be in a tight corner.

Explanation:

An idiom is a phrase or expression whose meaning cannot be understood from the literal meanings of its individual words. Let's analyze the meaning of the given options to find the best match for the underlined phrase "in a difficult situation":

1. Be in a tight corner: This idiom means to be in a difficult, awkward, or dangerous situation where escape or resolution is hard. In the context of the sentence, after the pandemic, the business crumbled, placing him in a very difficult financial and personal situation. Therefore, this is the most appropriate idiom.

2. Bolt from the blue: This phrase refers to a sudden, unexpected, and usually unpleasant event or piece of news.

3. Give a cold shoulder: This means to intentionally ignore, reject, or treat someone in an unfriendly manner.

4. Pull the last straw: Often referred to as "the last straw," this means the final problem in a series of troubles that causes a situation to become intolerable or collapse.

Thus, the idiom that accurately replaces "in a difficult situation" is Be in a tight corner.