Tom has a meeting this afternoon, but he's feeling sick. He ___ unable to attend the meeting.

• A. Will be
• B. Would be
• C. Could be
• D. Should be

Answer: (A)

Expressing a definite future outcome is the idea here. The sentence sets a future time (this afternoon) and explains a reason (he’s feeling sick) for why he won’t attend. “Will be unable to attend” communicates that, based on his current condition, he will in fact not be able to make the meeting. This is a straightforward, future-tense statement of fact.

The other options suggest ideas that don’t fit. “Would be” sounds conditional or hypothetical, not a definite future outcome. “Could be” expresses possibility, not certainty. “Should be” implies expectation or obligation, which isn’t about his actual inability due to illness.