+1 for

E.

Stimulus :

Premise : Math test's scores were lower this year than in previous years

Premise : This year, all students took math courses during the first period of the school day (students are NOT fully awake during the first period)

Premise : Last year, they had taken math during the final period of the day (students are fully awake during the final period)

Conclusion : Students perform better on math tests when they are fully awake, an so the headmaster believes that test scores would be higher if math classes were moved to the end of the day for students are fully awake during the final period.

(E) Students are more likely to be fully awake during the final period of the day than they are during the first period of the day. -->

Correct, negate the statement and see how it affects the conclusion.Hence,

E.

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