4

Set 5: Form, Structure & Sense (Advanced)

Explanation

Answer: A

PASSAGE

The telescope's sensitivity, enhanced through recent upgrades to its optical _______ now allows astronomers to detect exoplanets previously beyond the instrument's capabilities.

Which choice completes the text so that it conforms to the conventions of Standard English?

A. systems,✓ Correct
B. systems:
C. systems;
D. systems

Detailed Answer Explanation

This question tests your understanding of sentence function and text organization. The phrase 'enhanced through recent upgrades to its optical systems' is parenthetical. A comma closes this phrase before 'now allows.' Each sentence in a well-constructed text serves a specific purpose. Consider what role this sentence plays in the argument: does it introduce, support, contrast, or conclude an idea? Understanding why an author includes specific sentences helps you grasp the overall argument. Each sentence should serve a clear purpose: introducing ideas, providing evidence, acknowledging counterarguments, or drawing conclusions. Identify the role to understand the structure.

Key Evidence:

• "The telescope's sensitivity, enhanced through recent upgrades"

• "now allows astronomers"

Why others are wrong: B (A colon doesn't fit for closing a participial phrase.), C (A semicolon is too strong for closing a participial phrase.), D (Missing punctuation fails to close the parenthetical phrase.).