What is the sum of 15 and 10?

The sum of 15 and 10 is determined by adding these two numbers together. When you add 15 and 10, you can visualize it as counting up from 15. If you take 15 and increment it by 10, you are effectively combining the quantities.

So, if you start at 15 and add 10, you can think of it as follows:

15 + 10 = 25

Therefore, the correct sum is 25, which confirms that the chosen answer is accurate. The other options do not correctly represent the addition of these two numbers, as they do not equate to the total reached when performing the sum.