曼哈顿一题逻辑求问

Everyone who has graduated from TopNotch High School has an intelligence quotient (IQ) of over 120. Most students with an IQ of over 120 and all students with an IQ of over 150 who apply to one or more Ivy League universities are accepted by at least one of them.

The statements above, if true, best support which of the following conclusions?

	A	Every graduate of TopNotch High School with an IQ of 150 has been accepted by at least one Ivy-League university.
	B	If a person is a high-school graduate and has an IQ of less than 100, he or she could not have been a student at TopNotch High School.
	C	If a person has an IQ of 130 and is attending an Ivy-League university, it is possible for him or her to have graduated from TopNotch High School.
	D	At least one graduate from TopNotch high school who has applied to at least one Ivy-League university has been accepted to one of them.
	E	If a high-school graduate has an IQ of 150 and is not attending an Ivy-League university, then he or she did not apply to one of them.

答案是C，可以理解，但是B不是很能理解什么意思，贴一下解释

B.The passage states that every graduate of TopNotch High has an IQ of over 120. The conclusion only states that the student is a high school graduate and that he has an IQ of less than 120. It does NOT state that he or she was a graduate of TopNotch High. It is possible, however, that after attending TopNotch High for a period of time, he or she graduated from another high school. If this is the case, the situation does not contradict the passage, but contradicts the conclusion (he or she was a student at TopNotch High). Hence, this conclusion is not valid.