TOM REGRETTED _____ THE SECOND-HAND CAR; IT'S USELESS.A. BUYING B....

15. - KIEM TRA 15 456 ANH 11
KIEM TRA 15 456 ANH 11

15. Tom regretted _____ the second-hand car; it's useless.

A. buying B. to buy C. about buying D. bought