The molar conductivity of a $0.01 \text{ M}$ monobasic acid at $25^{\circ} \text{C}$ is $15 \text{ } \Omega^{-1} \text{cm}^2 \text{mol}^{-1}$. The molar conductivity of the same acid at infinite dilution is $375 \text{ } \Omega^{-1} \text{cm}^2 \text{mol}^{-1}$. Calculate the concentration of $[H^+]$ in the solution.

• A
  $2.0 \times 10^{-4} \text{ M}$
• B
  $3.0 \times 10^{-4} \text{ M}$
• C
  $4.0 \times 10^{-4} \text{ M}$
• D
  $5.0 \times 10^{-4} \text{ M}$