A prerequisite for the survival of life on land was the accumulation of
a. O2 in the atmosphere.
b. CO2 in the atmosphere.
c. water vapor in the atmosphere.
d. O3 in the atmosphere.
e. bacteria in the soil.
Answer: D
A prerequisite for the survival of life on land was the accumulation of
a. O2 in the atmosphere.
b. CO2 in the atmosphere.
c. water vapor in the atmosphere.
d. O3 in the atmosphere.
e. bacteria in the soil.