The number of positive integers which can be formed by using any number of digits from 0, 1, 2, 3, 4, 5 without repetition.

Answer: Option D

One digit positive numbers = 5
Two digit positive numbers = 25
Three digit positive numbers = 100
4 digit positive numbers = 300
5 digit positive numbers = 600
Six digit positive numbers = 600
Total positive numbers,
= 5 + 25 + 100 + 300 + 600 + 600
= 1630