To solve this question, the user needs to find the pattern or rule that generates the sequence of numbers. One way to do this is by calculating the difference between each pair of consecutive numbers in the sequence and see if there is a constant difference. If there is, the user can use this difference to find the next number in the sequence.

Let's calculate the differences between each pair of consecutive numbers:

15 - 8 = 7

24 - 15 = 9

35 - 24 = 11

48 - 35 = 13

63 - 48 = 15

We can see that the differences are increasing by 2 each time. Therefore, we can assume that the next difference is 17. To find the next number in the sequence, we add this difference to the last number in the sequence:

63 + 17 = 80

Therefore, the answer is option B, 80.

Option A, 70, is incorrect because it does not follow the pattern of the sequence.

Option C, 75, is incorrect because it also does not follow the pattern of the sequence.

Option D, 88, is incorrect because it is the result of adding 25 to the last number in the sequence, which does not follow the pattern of the sequence.