The Two Progressive Waves Are Moving with Equal Velocities and Wavelengths

Multiple Choice

The two progressive waves are moving with equal velocities and wavelengths but in opposite directions in the string. Which of the following gives all of the points that will be nodes in the resultant standing wave?

A) 2, 4, 6, 8, and 10
B) 2, 6, and 10
C) 1, 5, and 9
D) 3 and 7
E) 1, 3, 5, 7, and 9