The Natural Frequencies for a Stretched String of Length L

Multiple Choice

The natural frequencies for a stretched string of length L, and wave speed v, are Nv/(2L) where N equals

A) 0, 1, 3, 5, ...
B) 1, 3, 4, 5, ...
C) 1, 2, 3, 4, ...
D) 2, 4, 6, 8, ...
E) 0, 1, 2, 3, ...