问一道题：NO.PZ2018062007000010 [ CFA I ]

NO.PZ2018062007000010问题如下Whiof the following statements about cret rivative is most correct? A.a cret protection buyer provis protection to a seller against a specific cret loss. B.a cret protection seller provis protection to a buyer against a specific cret loss. C.the clearing house provis protection to a buyer against a pecific cret loss. B is correct.A cret rivative is a class of rivative contracts between two parties, a cret protection buyer ana cret protection seller, in whithe latter provis protection to the former against a specific cret loss.对于信用衍生品来说，如果发生cret loss，是由卖方支付给买方相应的损失，而不是由clearing house，所以正确是请问这一题目涉及到哪个知识点呢？