Final answer:
The set of positive multiples of 10 includes all positive whole numbers obtained by multiplying 10 by another positive whole number(option a).
Step-by-step explanation:
The set of positive multiples of 10 includes all positive whole numbers that can be obtained by multiplying 10 by another positive whole number.
For example, the first few multiples of 10 are 10, 20, 30, 40, 50, and so on.
Therefore, the answer is option a. The positive multiples of 10.