D because if the species was to be removed from an ecosystem, everything that needed that species as food, or the species ould have to adapt to the foods available in the new ecosystem they live in. Hope I helped, and let me know if you are still not 100% sure about the answer, and I'll try to clarify what I said.
The gamete that contains genes contributed only by the mother is an egg
D.
They break down dead organisms.
Cacti and other succulents can adapt to dry climates. They are able to store water in their leaves, while others store water in the roots or trunks. The waxy cuticle helps prevent water loss.
