Question

The macromolecule RNA is common to all living beings, and DNA, which is found in all organisms except some bacteria, is almost as BLANK. Select the two answer choices that, when substituted for the BLANK, fit the context and produce the two sentences most nearly alike in meaning.
(A) comprehensive
(B) fundamental
(C) inclusive
(D) universal
(E) significant
(F) ubiquitous

Hint:

Pay attention to comparison and parallel structures. Words like "and," "similarly," "like," and "as" often indicate that the blank requires a word that echoes a concept already mentioned in the sentence.

Answer 1

Step 1: Understanding the Concept:
This sentence equivalence question uses a parallel structure to define the blank. We need to find two words that describe DNA's prevalence, similar to how RNA is described.
Step 2: Detailed Explanation:
The sentence establishes a baseline: "RNA is common to all living beings." The word "and" and the phrase "almost as" indicate that the word in the blank should have a similar meaning to "common to all." We are looking for words that mean "widespread" or "found everywhere."
Analyzing the Options:
(D) universal: This word means relating to or done by all people or things in the world or in a particular group. In a biological context, it means found throughout the living world. This is a perfect match.
(F) ubiquitous: This word means present, appearing, or found everywhere. It is a direct and strong synonym for "universal" in this context.
The other options do not fit as well:
(A) comprehensive / (C) inclusive: These words refer to containing all elements, not being present in all places.
(B) fundamental / (E) significant: These words mean "important" or "basic." While DNA is both, the sentence's logic is about its prevalence, not its importance.
Step 3: Final Answer:
Both "universal" and "ubiquitous" accurately describe DNA as being nearly as widespread among living things as RNA is, thus completing the sentence's comparison logically.