Many experiments on Earth's early atmosphere have resulted in the formation of organic molecules, but none have resulted in cell formation. In which of the following ways do the experimental conditions prevent cell formation in the lab? A: The ultraviolet light intensity of Earth's early atmosphere cannot be reproduced.

B: The gas composition of Earth's early atmosphere cannot be replicated.

C: The nutrients of Earth's early atmosphere are different from those found today.

D: The experiments cannot last for billions of years as conditions did in Earth's early atmosphere.