Choose the underlined word or phrase in each of the sentences that need correcting.
1. ALTHOUGH (A) being only 14, she WAS (B) MORE MATURE (C) than MOST OF (D) her classmates. 
2. We do not OWN (A) the building. THUS (B), it would be POSSIBLE (C) for us TO MAKE (D) any major changes to it.
3. After OBTAINING (A) a degree IN PHYSICS (B) she went BACK (C) to take ANOTHER (D) degree in mathematics.
4. The NOISE (A) of my NEIGHBORS' (B) quarrel STOPPED (C) me from GOING OUT (D) to sleep.
5. Lizzie TOLD (A) me that it WAS (B) the LOVELIEST (C) gift she EVER RECEIVED (D).
6. SURPRISINGLY (A), someone HAD CHANGED (B) the curtains BEFORE (C) I HAD ARRIVED (D)
7. HAD ENTERED (A) my HOUSE  (B), they WENT (C) straight INTO (D) the dining room.
8. SINCE (A) her accident, she HAD (B) always suffered FROM (C) constant HEADACHES (D).
9. We ARE GOING (A) to STUDY (B) tonight UNTIL (C) we WILL FINISH (D) this chapter.
10. ONLY (A) in THE LAST (B) few years PEOPLE HAVE BEGUN (C) TO USE (D) home computer.
11 HAVE (A) you heard THE NEWS (B) ? The President has BEEN (C) SHOOTING (D) !
12. They ARE GOING TO (A) have to LEAVE (B) soon, and SO DO (C) WE (D).
13. NOT UNTIL (A) the early 1960s, DID THE BIRTHRATE (B) in the United States BEGAN (C) TO DECLINE (D).
14. I'll FLY (A) to MARS (B) next week. I'VE ALREADY (C) gotten A (D) ticket.
15. Look! THAT (A) plane IS FLYING (B) TOWARDS (C) the airport. It IS LANDING (D).
16. Many insects MAKE (A) sound BECAUSE (B) THEY HAVE (C) no vocal apparatus IN THEIR THROATS (D).