Select the number from among the given options that can replace the question mark (?) in the following series.
15,20,45,170,?

Let's find the difference pattern between consecutive terms of the series:
20−15=5

45−20=25

170−45=125

The differences are powers of 5:

5=5
1


25=5
2


125=5
3


Following this pattern, the next difference must be 5
4
=625.

Therefore, the next number in the series will be:

170+625=795