1

Problem

He thought long and hard before making his decision one-that would affect the rest of his career and potentially change the course of his life.

2

Clue

To determine the correct punctuation, identify whether the phrase “one that would affect the rest of his career…” renames or further defines the noun decision. When a second phrase restates or expands the noun directly, the appropriate punctuation must signal an interruptive explanatory appositive, not a separation into new clauses.

3

Hint

When a phrase renames or further explains a noun in a dramatic or emphatic way, an em dash (—) is preferred to introduce the explanation.

4

Sumup

Please summarize Problem, Hint, Clue

Choices

5

Choice-A

Choice A is incorrect. The phrase “decision one-that” is punctuated incorrectly; the hyphen after “one” and the missing punctuation before “one” make the sentence grammatically confusing and interrupt the flow of meaning.

Wrong No change

6

Choice-B

Choice B is incorrect. An apostrophe after “decision” incorrectly signals possession or omission, neither of which is intended here. The semicolon after “that” creates unnecessary separation and incorrectly suggests two independent clauses.

Wrong decision' one that;

7

Choice-C

Choice C is incorrect. A colon can introduce a list or an explanation, but only when positioned after a complete clause. Here, “decision” alone is not a complete clause, so the colon is grammatically inappropriate.

Wrong decision: one that

8

Choice-D

Choice D is correct. An em dash smoothly introduces the explanatory phrase “one that would affect the rest of his career and potentially change the course of his life,” clarifying and emphasizing what kind of decision it was.

Correct decision—one that

9

Step

Correct answer: He thought long and hard before making his decision—one that would affect the rest of his career and potentially change the course of his life.

10

Answer

Option

D

11

Sumup

Please summarize choices