The answer is B: dies instantly from a car accident.
Explanation for each option:
A. Injured in a skiing accident and dies 18 months later - Incorrect. Double indemnity typically covers accidental deaths, but the death must occur within a certain time frame after the accident, often 90 days. Since Matt died 18 months later, this would not qualify for double indemnity.
B. Dies instantly from a car accident - Correct. Double indemnity riders usually pay out when the insured dies as a result of an accident. A car accident resulting in immediate death would typically qualify for this benefit.
C. Dies of a stroke - Incorrect. A stroke is considered a natural cause of death, not an accident. Double indemnity benefits are generally only payable for accidental deaths.
D. Killed while committing a felony - Incorrect. Most life insurance policies, including those with double indemnity riders, have exclusions for deaths that occur while committing a felony. Therefore, this situation would not qualify for the double indemnity benefit.
In summary, the correct answer is B, as it aligns with the typical conditions under which a double indemnity rider would pay out.