PSAT Reading Question 563: Answer and Explanation

Question: 563

According to the passage, which characteristic of a comet is most essential to its being categorized as a "Great Comet"?

• A. Whether it has a significant proportion of dust and ice in its core
• B. Whether it has an orbital eccentricity greater than zero
• C. Whether humans can observe it without a telescope
• D. Whether it contributes to meteor activity visible by astronomers

Correct Answer: C

Explanation:

(C) Lines 8–10 define a Great Comet as one that is bright enough to be observed by people on Earth with the naked eye. Although the other options may be attributes of a Great Comet, they are not, by definition, necessarily attributes.