For a living organism, which of the following are true? select all that apply
a the ratio of c-14 to c-12 remains constant.
b the ratio of c-14 to c-12 increases over time.
c the ratio of c-14 to c-12 decreases over time.
d the amount of c-14 is less than the amount of c-12.

123/33

explanation:

because i added numbers

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

explanation:

i didn't have the answer choices , but i tried my best.