听一段短文，根据短文内容选出正确的答案
11．What was the main reason for people to have dogs in the past？
A．To make money．
B．To make them safe．
C．To help them work．
12．What do many people walk with in the park？
A．Pigs．
B．Goats．
C．Dogs．
13．What's a dog for a child？
A．A smart teacher．
B．A helpful brother．
C．A playmate．
14．What do young people regard a dog as？
A．A friend．
B．A teacher．
C．A child．
15．What do old people regard a dog as？
A．A friend．
B．A teacher．
C．A child．