I chose A and got it wrong.

However, while analyzing the question again arrived at E, very easily.
here is how, one can get the answer

Premise: Most of the students who took Spanish 101 at the University last semester attended every class.
Premise: However, each student who received a grade lower than B minus missed at least one class session.



Now let's rephrase the premise1:
Most is more than 50%, that means, premise is saying, 51% of the students who took Spanish attended every class in last semester.
it clearly means, there are 49% students who missed one or more classes. And those who missed one or more classes received a grade lower than B minus.

So premise 1 understanding tells us that most of the students = 51% of the students =more than half of the students received a grade higher than B.
That's what E is saying.
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Both A and E both seem correct but what is wrong with A?

Most of the students who took Spanish 101 at the University last semester attended every class. However, each student who received a grade lower than B minus missed at least one class session.

What does the para tell us?
Most of the students who took Spanish 101 at the University last semester attended every class.: It also means that only few missed one or more classes.
each student who received a grade lower than B minus missed at least one class session.: This means no one who attended all classes got less than B-

There is nothing more to the para, so do not get confused in the groups. We can talk of one group :-
1) Below B- : Missed at least one class

Which one of the following statements about the students who took Spanish 101 at the university last semester can be properly inferred from the information above?

(A) At least some of the students who received a grade of A minus or higher attended every class session.
That is nowhere mentioned. As I said, be careful with the groups we are looking at. We know only about one group: Below B-.
It may be possible that very few got A- or higher and these were the brainy ones who missed one class or more and still got A+. Nothing has been told about this group.
It could be that MOST of the class got a B and these included everyone who attended all classes.

(B) Most, if not all, of the students who missed at least one class session received a grade lower than B
Do not get confused in the two groups, namely group X of students who got less than B- and group Y of students who missed at least one class.
Remember Venn Diagram. X is subset of Y, but Y may have much more than the group X.
May be ONLY one got B-, and the remaining of group Y got A.

(C) Most of the students received a grade higher B minus.
We could say B- and higher, but not higher than B-. may be all those attended all classes got B-, and remaining who missed at least one class got less than B-.
What do we have here?: No one got a grade higher than b-.

(D) At least one student who received a grade of B minus or higher missed one or more class sessions.
We got a situation opposite of this in option C.

(E) More than half of the students received a grade of B minus or higher.
Now, this follows our thought process. We did speak of this in C.
Only few students missed one class or more, so let us take the worst case where all of Y group in option B get a grade less than B-. That is, X=Y.
So, even in the worst case scenario, remaining would have got a B- or higher, and we know that most of the students belong to this 'remaining' group.
MOST means MORE than half.
CORRECT


E
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I ended choosing up A and got it wrong. Have given my analysis above about arriving at E.
As far why A is NOT the correct choice... the answer would be both A and E are correct and E is more correct. (if you choose A, same question can be asked about E- what wrong with E)...
But still to have concrete answer, we cant deny possibility that people who attended every class got only a B grade or at max B plus, we can't infer from given information about whether they got A minus or higher.
Hence E stands out.

Hope this helps.
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