A heap of grapes is divided into groups of 3, 5 and 7 and each time one coconut is left over. The least number of grapes in the heap is?
A. 31 B. 41 C. 51 D. 61  Choose the correct choice from the following choices:
A) 31  B) 41  C) 106  D) 61  E) 71

Rationale: lcm = 105 = > 105 + 1 = 106 answer : c
Answer: C