A) Single-stranded RNA can have many shapes.
B) Replication of RNA is flawless.
C) Some strands of RNA replicate more often than others.
D) Some strands of RNA are extremely chemically stable.

A) the ability to synthesize enzymes
B) a surrounding membrane or membrane-like structure
C) RNA genes
D) the ability to replicate RNA

A) Lightning and UV radiation were abundant in the early Earth atmosphere.
B) Some evidence suggests that the early atmosphere was made up primarily of nitrogen and carbon dioxide.
C) Remnants of amino acids were discovered near volcanic eruption sites.
D) Modern experiments show that organic compounds were probably produced in deep-sea hydrothermal vents.