The synthesis of DNA and RNA from the organic soup would have been guided by the actions of enzymes in the

A. clay-catalyst hypothesis
B. protein-first hypothesis
C. RNA-first hypothesis
D. chloroplast

Fossils used to identify geological periods are _________ fossils.

A. index
B. body
C. trace
D. stromatolite

Some viruses never use DNA to carry out protein synthesis and have only RNA as their genetic material. This would lend evidence to which theory?

A. endosymbiotic theory of eukaryote evolution
B. RNA-first hypothesis
C. simultaneous evolution of RNA & proteins
D. protein-first hypothesis