Answer:
adverb clause
Explanation:
Anytime you see the keyword modifies\modify, you will automatically know that it will be an 'adverb' answer.
I am joyous to assist you anytime.
I believe that the message the author is trying to convey in this excerpt is that humans need to take action to end further destruction of the natural environment, because if they don't, more and more species will disappear.
They have the same endings except in the nosotros and vosotros forms.