Platelets would help the blood clot, therefore preventing blood loss. White Blood Cells would help protect against infection. So, I believe the answer would be platelets & white blood cells.
Chargaff's rules state: adenine is complimentary to thymine and cytosine is complimentary to guanine. For this question, in order for polymerization of the growing complementary strand, guanine must bind with cytosine. <span>Answer: B.C</span>