Sentence Correction (SC) | Re: Monday’s test was said to be very difficult, so not only Matt but too

This is a case of idiom error. Idiom has to benot only X but also Y . Moreover since the first part of sentence is in past tense, the second part has to be also in past tense.
B and E uses present tense. C has awkward construction and does not uses idiom. Similarly A does not use the idiom correctly. D is correct

a) so not only Matt but too his friends had to study
b) so not only Matt but also his friendshave to study
c) so too Matt and also his riends they needed studying d) so not only Matt
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