Convert 3 feet to inches.

To convert feet to inches, it's important to know the conversion factor: 1 foot is equal to 12 inches. Therefore, when converting 3 feet to inches, you multiply the number of feet by the number of inches per foot.

3 feet × 12 inches/foot = 36 inches.

This calculation clearly shows that 3 feet equals 36 inches, making it the correct answer. Each of the other options does not accurately reflect the conversion based on the standard ratio of feet to inches.