Jack wasn’t in his own car.He was driving ___ car.

Jack wasn't in his own car.He was driving ___ car.
Jack wasn’t in his own car.He was driving ___ car.A) someone’s else B) someone else C) someone else’s D) someone’s else’s
答案选C为什么?选A为什么不行?

C
别人的（车）
else 修饰不定代词要后置,所有格只在else 后加‘s 即可,即 someone else's