A gradual increase in the world's average surface temperature is known as:

A) genetic pollution
B) industrial pollution
C) the decline of biodiversity
D) global warming
E) all of these choices

The gradual increase in the world's average surface temperature is specifically known as global warming. It is not directly related to genetic or industrial pollution, nor is it synonymous with the decline of biodiversity, which refers to the reduction in the variety and abundance of different species in an ecosystem.