Answer: C. "Complacent and Apathetic"
Explanation:
By definition it would be "Complacent and Apethetic"
Blithe: A casual and cheerful indifference; happy or joyous.
Complacent: Smug/Uncritical satisfaction with oneself or achievements.
Apethetic: Showing/Feeling no interest or concern.
By context of the poem it seems everyone is peacefully indifferent and happy with what they were doing.
Answer: A
The most relevant piece of evidence for this claim is option A. Option A is the only one that specifically describes how our lives have improved due to the exploration of outer space. Option B tells us about changes, but does not state that the changes have been positive. Option C describes exploration, but does not describe how we have benefitted from it. Finally, option D discusses the benefits we might someday experience, but not the ones we already enjoy in the present.
I believe the answer is c