☁️My Answers☁️:
4.) c. will see
I believe this is correct because in the sentence he says he will see his doctor tomorrow and that means it is in the future so the word 'will' is to show he will go to see his doctor tomorrow.
5.) c. used to dance
I believe this is correct because the sentence is using past tense by saying "I remember when..." because by saying I remember that means your remembering something that happened in the past which is why c is the correct answer.
6.) c. has been watching
I believe this is correct because the sentence is using present tense by saying that he has been reading an article which means he still is.
7.) a. I will be able to
I believe this is correct because the sentence is using future tense again by saying he will call the person tomorrow which means this is a good option to put because the word will since will is a future tense word as well.