Answer:
Producing toxic substances to suppress host response
The air begins to rise into the atmosphere. When air rises, it cools down and condenses into precipitation and clouds. This is why an approaching low pressure system means an increased chance for clouds, rain, or snow. It is called "low pressure" because as air rises, the air pressure is lower at the surface.
Functional and economically most important mineral in nutrition of layers
is calcium, primary because of egg production, i.e. forming of the egg shell.
D. Predators
Predators keep populations of other species in check. This was pretty clearly demonstrated in Yellowstone National Park after the wolves were eradicated there. The deer populations increased to the point that the aspen trees nearly disappeared due to the saplings' being eaten by deer. Since the reintroduction of wolves to the park, the aspen trees have begun to flourish once again.
B is correct, Organisms in the same group have similar characteristics