The couple … their first child when I entered college.

Analyze the question

The sentence is: "The couple ___ their first child when I entered college." It tests tense agreement, specifically the use of the past perfect to show that one past action happened before another past action.

Explain the concept

• "I entered college" is a simple past action, a fixed point in the past.
• If something had not yet happened before that point, we use the past perfect: had/hadn't + past participle.
• Example: "She hadn't arrived when the meeting began." (Her arrival would have come before the meeting began, but it didn't happen.)

Step-by-step solution

1. The time reference is "when I entered college," which is in the simple past.
2. The couple's having a first child is described relative to that time. It had not happened up to that point, so the past perfect is the best fit: hadn't had.
3. Check the other options: • A. hasn't had is present perfect and singular. It does not fit a past time reference and does not agree with "couple" here. • B. haven't had is present perfect. It clashes with the past time "when I entered college." • C. were not having is past continuous. "Have" meaning "give birth to" is not normally used this way, and it doesn't show an earlier completed or non-completed state. • D. hadn't had is past perfect. It fits the past time reference and expresses that the event had not happened before then.

Answer: The correct option is D. hadn't had.

Full sentence: "The couple hadn't had their first child when I entered college."

Tip: When you see a past action introduced by when, before, or by the time, ask yourself whether another action happened earlier. If it did, use the past perfect (had + past participle). Present perfect forms such as has/have almost never go with a clearly past time reference.