RNA is Believed to Have Preceded DNA Because _____

Question

RNA is believed to have preceded DNA because _____.  
A) DNA contains thymine and RNA does not.
B) DNA is double stranded and requires more components.
C) DNA can store more protein-building instructions in less space.
D) RNA can also function as an enzyme.
E) RNA cannot replicate itself.

Accepted Answer

RNA is believed to have preceded DNA because it can function as an enzyme, which suggests it could have catalyzed its own replication and other biochemical reactions in early life forms.