Calculate the [H⁺] in an Aqueous Solution That Is 0

Calculate the [H⁺] in an aqueous solution that is 0.0755 M HF and 0.100 M NaF.The value of K_a for HF is 3.5 * 10^-4.

A) 4.6 * 10^-4 M
B) 2.6 *10^-4 M
C) 3.5 * 10^-4 M
D) 0.176 M
E) 0.0755 M