Hey, this may be really late...but I'm going through the English section on brainly and found your question...
Your answer is B. "His rays had slain one who was too greatly daring."
Explanation:
Before this quote the story goes, "Then the car of Apollo drove on." This "car" is actually the sun chariot which Apollo drives. The quote is saying that the sun's rays killed Icarus for "being too daring". This is concluded because he wanted to keep flying higher and higher until he got too close to the sun.
