If he the textbook like he was supposed to, he would have known what was on the test. a. will have read

b. shouldn’t have read

c. would have read

d. had read

B. would have read

Explanation:

Because it's asking what is he saying so I have to be B.

If he (d.) had read the textbook like he was supposed to, he would have known what was on the test.

Explanation:

It's either this or (c) but im pretty sure it's (d) lol

hope someone can help better

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