第二部分：題組
（19-20）
          How serious is the problem of stray dogs in Taiwan? The news says that, from 1999 to 2008, about 900,000 stray dogs were sent to animal shelters, but only 16% of them found new homes. About 73% of them were killed after they had stayed in the shelters for seven days. Every year, over 300,000 dogs become homeless. It’s sad, isn’t it? So, if you really want to keep a dog, please adopt one from an animal shelter； give it a real home and never let it go stray again.
 ☞ adoopt領養 shelter收容所
【題組】19.What does stray mean here?
(A) killed
(B) sick
(C) serious
(D) homeless