Answer:
A is correct external fertilisation doesn't require sexual intercourse
The white blood cell is called NEUTROPHIL. Neutrophils play important roles in the immune system; they move around the body via the blood stream and when they sense signals that foreign bodies are present, they move to the site of the infection and destroy them. They are among the first set of immune cells that defend the body against infection.
Answer:
The animals could change it. For example, a bunny could dig a hole in the ground, making a home for other animals inside of it, too, changing the animals' living environment.
Or natural disasters could change their environment, too. For example, if a landslide occurred and covered a pond, frogs and snakes could lose their living areas and food, which would make them have to move to a different area, changing another ecosystem.
What contains the different kind of molecules is the answer is D