Your answer is C, emissions!
The second sentence, "I love vanilla ice cream, but my sister likes butter pecan," has the correct punctuation. In a compound sentence, the comma always goes before the coordinating conjunction (In your case, this conjunction was "but.").
A good answer would be the last; it shows evidence and statistics, and proves the counter-arguement invalid because not everything would be replaced.
Think it this way. Should humans know everything or about everything, or are there certain things humans shouldn't know about?
Answer:
A
Explanation:
I really can't explain stuff easy. sorry.
