Why didn't you go to school yesterday? 1) I didn't see you there. 2) I had a great time. 3) I will see you tomorrow. 4) I was not feeling well.

The question is "Why didn't you go to school yesterday?" which translates to "Почему ты не пошел в школу вчера?" Therefore, the most appropriate answer from the given options is:

"I was not feeling well." (Мне было нехорошо.)

Correct answer: 4