催化药物S-甲基化反应的重要酶是（）
A.巯甲基转移酶
B.乙醇脱氢酶
C.两者均是
D.两者均否
参考答案：A
已知△ABC中，a=3，b=5，c=7，，则角C=______．
A joint probability of A and B must always be:（）
A. less than or equal to the conditional probability of A given B.
B. greater than or equal to the conditional probability of A given B.
C. greater than or equal to than the probability of A or B.
