Calculate the activity coefficient of H⁺ using the extended Debye-Huckel equation for a solution comprised of H⁺ and I ^–. Given that H⁺ has a size of 9.00 x 10^-10 m and the molar concentration of the solution is 0.075. 

log γ = − 0.51 z ² √µ / 1 + (α √µ / 305)

• A. 0.917
• B. 0.982
• C. 0.837
• D. 1.49