Question

and he allowed his own reputation to be ruined in a vain effort to save mr. edwards from embarrassment. source: new york times in this sentence, vain means: unproductive of success not as expected far apart in relevance or relationship or kinship not to be altered or undone

Explanation:

The context shows that his effort to save Mr. Edwards from embarrassment was unsuccessful as he ruined his own reputation. "Vain" here implies the effort did not lead to success.

Answer:

A. unproductive of success