What happened as a result of higher oxygen levels millions of years ago? (A)
Flowers started to be pollinated by bees.
(B)
Many insects had shorter lifespans than they have today.
(C)
Many insects grew to be bigger than they are today.
(D)
Flowers were unable to produce nectar.

A Flowers started to be pollinated by trees.

Explanation:

Hopefully this helps

i'm gonna put a couple so you can chose from

explanation:

if you know the fur color of the offspring mice, you can use the ratios to identify the genotypes of the parents.

if either parent mouse passes a dominant allele, the offspring will have black fur.

if the parental mice has two different fur color (i.e white and black) , the color of the offspring's fur would be either black, white, or the combination of both (grey)

hope this : )