Correct Answer: A
Explanation:
The best choice is A. After reading the sentence, you may decide that the phrase not apparent at the time would suggest looking back for the first blank and that the second word needs to be affected. You could read the sentence "Although it was not apparent at the time, in looking back we can see how Ustad Bankey Khan’s performances in the 1970s were affected by what was happening then in popular music." Now, looking for synonyms for looking back and affected gives you choice A retrospect .. influenced.
| Retrospect: | a looking back on or thinking about things past |