What is another term for the manipulated variable?

Fossils found in strata reveal that a) innate drive to complexity of life b) unused body parts decrease in size c) older strata carry fossils that differ greatly from living organisms d) geologic changes occur quickly on earth

Anybody who knows ap biology, can you friend or message me

Hurry where is the majority of earth's water found? o glaciers o oceans ground o rivers and lakes