问题

The number of the cranes is getting ______.If we don’t help them, they will disappear ________a few years.
A:S+V
B:S+V+DO+OC
C:S+V+P
D:S+V+IO+DO;
B:S+V+DO+OC
C:S+V+P
D:S+V+IO+DO;
正确答案是: