Why do you think UV intensity changes with latitude?

Because of the angle of the Earth relative to the sun. The higher the sun is in the sky, the higher the UV radiation level.

Explanation:

So, the lattitudes toward the poles that receive sunlight are at an oblique angle, with that being said, the amount of radiation is spread to a larger area than the equator.

oceans

indian ocean

pacific ocean

atlantic ocean

arctic ocean

southern ocean

the answer to your question is:

c. complementary base-pairing