How many diagonals does a polygon with 15 sides have, if one of its vertices does not connect to any diagonal?	Choose the correct choice from the following answers.
A) 80	B) 90	C) 77	D) 88	E) 99

Rationale: if i calculate it using the formulae , # diagonals = n ( n - 3 ) / 2 each vertex sends of n - 3 diagonals n = 15 - 1 then 14 * ( 14 - 3 ) / 2 = 77 correct option : c
Answer: C