单项选择题

[听力原文]
W: Your bike looks quite new. When did you buy it
M: My mother bought it for me when I was ten years old. Now, I’m already 20 years old.

How long has the man used his bike()

A.About 10 years.
B.About 8 years.
C.About 20 years.
D.About 12 years.