Choose the underlined word or phrase (A, B, C or D) that needs correcting

Choose the underlined word or phrase (A, B, C or D) that needs correcting.

29. Mr. Smith(A) is going to buy(B) a new Japanese(C) cars, doesn’t he(D)?

30. I met(A) a lot of interesting(B) people while(C) I was studying at(D) Ho Chi Minh City.