Vocabulary – Choose the option that BEST expresses the meaning of the underlined word in context. Sentence: The inspector was a vigilant young man.

Introduction / Context:
“Vigilant” describes a state of careful watchfulness, alertness, and readiness to notice danger or problems. For roles like inspectors, guards, and auditors, vigilance is a key professional attribute.

Given Data / Assumptions:

• Target word: vigilant.
• Context: personal attribute of an inspector.
• We must find the closest synonym.

Concept / Approach:
Among the choices, “watchful” directly expresses vigilant’s core meaning. “Intelligent,” “ambitious,” and “smart” relate to cognitive ability or drive, not sustained alertness.

Step-by-Step Solution:
Define vigilant = alert, watchful, on guard.Scan options: “watchful” is a direct synonym; others address different traits.Select the precise match.Confirm by substitution for naturalness.

Verification / Alternative check:
Substitute: “The inspector was a watchful young man.” The sentence remains accurate and idiomatic.

Why Other Options Are Wrong:

• intelligent: about intellect, not alertness.
• ambitious: about drive/aspiration.
• smart: informal for clever or well-dressed; not the same as vigilant.

Common Pitfalls:
Choosing “intelligent” because inspectors often are; the word tested is about alertness, not IQ.

Final Answer:
watchful