For any real number x, [x] denotes the largest integer less than or equal to x.
For example, [4.2] = 4 and [0.9] = 0. If S is the sum of all integers k is divisible by [\sqrt k], then S equals
Answer Choices
A. 999\:500\:000
B. 999\:000\:000
C. 999\:999\:000
D. 998\:999\:500
E. 998\:500\:500