Two Tiny Metal Spheres Are Fixed to the Ends of a Non-Conducting

Two tiny metal spheres are fixed to the ends of a non-conducting string of length . Equal charges, +q, are placed on the metal spheres. Randall says that the force on the string has magnitude . Tilden says that the tension in the string has magnitude . Which one, if either, is correct?

A) Randall, because both charges exert forces on the string, but the tension is
.
B) Tilden, because both charges exert forces on the string, but the net force is
.
C) Both are correct, because both charges exert forces on the string.
D) Neither is correct, because both the tension and the force have magnitude
.
E) Neither is correct, because the tension is
, but the net force is 0.