Despite its low net primary productivity (NPP), the open ocean produces more of the earth's biomass per year than any other ecosystem or life zone because of the enormous volume of the global ocean
growth is not limited by nutrient availability
more sunlight is available
there are fewer primary consumers
whales are so large

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

i think the answer is b.

answer;

-vessels in the chest

the diagnosis of angina pectoris literally means "vessels in the chest"

explanation;

-angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease.it is the chest pain due to an inadequate supply of oxygen to the heart muscle. the pain is typically severe and crushing, and it is characterized by a feeling of pressure and suffocation just behind the breastbone.

agina pectoris is caused by reduced blood flow to your heart muscle. the blood carries oxygen, which the heart muscle needs to survive. when the heart muscle isn't getting enough oxygen, it causes a condition called ischemia