In the question, a part of the sentence is printed in bold. Below are given alternatives to the bold part at (1), (2), (3) which may improve the sentence. Choose the correct alternative. In case no improvement is needed your answer is (4).
After twenty years of exile, the prisoner was in the end of his tether.

Options

A. on
B. though
C. at
D. No improvement

Answer

C

Explanation

Be at the end of your tether means: to feel that you cannot deal with a difficult situation any more because you are too tired, worried etc.