Which of the following sentences is missing a comma?
A. The door was open and the window was broken.

B. On February 12, 1971, my brother was born.

C. At first, I didn't know what was going on.

D. The shed collapsed because the snow made the roof too heavy.

The answer is option A.

Explanation:

The door was open, and the window was broken.

to me i think class room sitting education is better. i do online school and i have not learned a think haha. when i sit in the classroom i just sit there and kind of pay attention but still i get so far ahead in the class when im doing online i have nothing else better to do but play video games and i sit in school and learn and have friends and just actually learn. when i'm doing online i sit here listing to music and get on and and look up the answers i guess that is my fault for being a cheater. but to be honest i think sitting in the classroom is better.