This is the sum when the series starts from 1. So, this is the wrong option~This is the sum of 1 + 2 + 3~This is the correct option. We find the sum of the series from 1 to 100 and then the sum of the series from 1 to 3. We then subtract the sum of the series from 1to 3 from the sum of the series from 1 to 100. What we get is the sum of the series from 4 to 100