Can someone please answer quick and correctly all three questions btw thxs I will give brainliest

Are substances released into the environment that in excess amounts cause damage

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.

Why should organisms reproduce more offspring than will survive? select all that apply.