Question

1. why are krill important in the polar ecosystem?

a. they help with ice formation
b. they form a major part of the food web
c. they fertilize the soil
d. they clean the ocean floor

Explanation:

In the polar ecosystem, krill are a key species in the food web. Option a is incorrect as krill don't help with ice formation. Option c is wrong because polar ecosystems have little soil for fertilization, and krill live in water. Option d is incorrect as krill don't clean the ocean floor. Krill are a major food source for many organisms like whales, seals, etc., so they form a major part of the food web.

Answer:

b. They form a major part of the food web