Which statement describes how the mantle is similar to Earth's oceanic crust?
A)It is composed mostly of basalt.
B)It consists primarily of molten rock.
C)It has varying degrees of thickness.
D)It is divided into two layers.

Which of the following statements about genes and traits is true? a single trait can be controlled by multiple genes. a single gene can control a single trait. a single trait can alter multiple genes. a single gene can influence multiple traits.