This is a grammar question on jtest4you grammar exercise 26. The answer choices are
A. 見ないこと
B. 見なかったこと
C. 見ないもの
D. 見なかったもの
I chose A but the answer is B. Both sounded correct to me. I do not understand why A is not grammatical. After a short amount of unsuccessful searching for past or present tense + ことにしよう I threw the correct answer into Google Translate and got, “Let’s pretend we didn’t see what was inside the box,” while for answer A I got, “Let’s not look at the contents of the box.” What is the problem with answer A?