The different pronunciation is B. planets.
The different pronunciation is C. controlled.
14. We should go ______ our homework and lesson notes several times before the test.
The correct phrasal verb is "go over," meaning to review or check something.
The correct answer is B. over.
15. ______ being spoken all over the world, English will be very helpful for you in the future.
"Because of" is followed by a noun or noun phrase. "Because," "since," and "as" are followed by a clause (subject + verb). In this case, we have a participle clause ("being spoken").
The correct answer is A. Because of.
16. When I was young, I ______ spend much time watching TV.
This describes a past habit. The correct tense is "used to."
The correct answer is A. used.