Available options:
1). evolving
2). protect them
3). recycling
4). ligt
5). animals
6). ferns
7). trees
8). heat
Q: Fact 1: Biodiversity increases the productivity and stability of ecosystems. Fact 2: Biodiversity is an incredibly powerful force that keeps species evolving. Given the two facts above, a force that keeps species what increases the productivity and stability of ecosystems?
A:
1).