Planting trees has a positive impact on an ecosystem.
Thus one important job the squirrel does in the ecosystem is to plant trees.
Squirrels have a positive effect on the ecosystem.
What kind of effect does a squirrel have on the ecosystem?
Options:
[a] Negative
[b] Positive
[c] adding heat
[d] growth
[e] food
[f] Destructive
[g] Powerful
[h] support