A:实践具有社会性的特点
B:实践是客观的物质性活动
C:实践是人类特有的活动
D:实践是能动地改造主客观世界的活动
下列不属于生态系统的是 ( )
There are fewer and fewer tigers in India. The situation will continue ______ humans stop hunting them for their fur and bones.