PQRSTU is a regular hexagon drawn upon ground. Prashant stands at P and he starts jumping from the vertex to vertex beginning from P. From any vertex of hexagon except S, which is opposite to A, he might jump to any adjacent vertices. When he reaches S, he stops. Let Sn be the number of distinct paths of exactly n jumps ending at S. What is the value of S2k, where k is an integer?
A. 0
B. 4
C. 2k
D. Depends on the value of k