In evolutionary terms, RNA is thought to have preceded proteins and DNA. Which of the following provides the most convincing support for this hypothesis?

a. there are more types of RNA than there are of DNA
b. RNA can both store genetic information and act as an enzyme
c. single stranded RNA is less structurally complex than double stranded DNA
d. viruses containing protein are among the oldest forms of life

B?

can't be A or C. It's either B or D.

The correct answer is B. RNA can both store genetic information and act as an enzyme. This is a key characteristic of RNA that supports the hypothesis that it preceded proteins and DNA in evolution. RNA molecules have the ability to store genetic information like DNA, but they can also catalyze chemical reactions like proteins. This suggests that early life forms may have relied on RNA for both information storage and functional activities. The versatility of RNA provides evidence for its potential precedence in evolutionary history.

To determine which option provides the most convincing support for the hypothesis that RNA preceded proteins and DNA in evolution, let's analyze each option:

a. There are more types of RNA than there are of DNA: While this statement is true, it does not provide direct evidence to support the hypothesis. The number of types of RNA is not necessarily related to the order in which these molecules evolved.

b. RNA can both store genetic information and act as an enzyme: This statement is significant. Unlike DNA, which primarily stores genetic information, RNA can function as both genetic material and enzymatic molecules called ribozymes. This supports the idea that RNA may have played a dual role in early evolution, acting as both coding molecules and catalysts.

c. Single-stranded RNA is less structurally complex than double-stranded DNA: Though this statement is true, it does not directly support the hypothesis that RNA preceded proteins and DNA. The difference in structural complexity is not sufficient evidence to determine order of evolution.

d. Viruses containing protein are among the oldest forms of life: This statement is not relevant to RNA preceding proteins and DNA as it primarily discusses viruses rather than the biological origin of RNA.

Based on the analysis, option b. RNA can both store genetic information and act as an enzyme, provides the most convincing support for the hypothesis. This is because it directly highlights the unique capabilities of RNA as a molecule that can fulfill the functions of both genetic storage and enzymatic activity.