At sea

Answer: Option A

Explanation:

Example : My brother is at sea in maths, he can not solve even the easy problems.

Answer: Option C

Explanation:

Example : He is in a flutter as he is going for PO interview.

Answer: Option A

Explanation:

Example : Brave people never despair when the church comes.

Answer: Option B

Explanation:

Example : It is the high time for the two brothers to bury the hatchet and mend their fences.

Answer: Option B

Explanation:

Example : We should take care of the rank and file in every policy we make in national interest.