Final answer:
The least common multiple of 3, 5, and 6 is 30, which is found by comparing the multiples of each number until the smallest common multiple is identified.
Step-by-step explanation:
To find the least common multiple (LCM) of 3, 5, and 6, we need to look for the smallest number that all three numbers divide into without leaving a remainder. The multiples of 3 are 3, 6, 9, 12, 15, 18, 21, etc. The multiples of 5 are 5, 10, 15, 20, 25, etc. And the multiples of 6 are 6, 12, 18, 24, 30, etc. By comparing these multiples, we can see that the smallest multiple that they all share is 30. Therefore, the least common multiple of 3, 5, and 6 is 30, which is option (D).