7. He housework after school at the moment. A. are doing B. does C. is doing D. will do

He is doing housework after school at the moment.
If the sentence ended at school, “does” would be correct, but it ends with “at the moment”, so “is doing” would fit the best, as it expresses that he is doing it at that exact time and not that he does it habitually, although he very well might; it just isn’t being expressed in the sentence.

Perpendicular line? no.