Potassium Hydrogen Phthalate (KHP) Is Used to Standardize Sodium Hydroxide $\leftrightharpoons$

Potassium hydrogen phthalate (KHP) is used to standardize sodium hydroxide. If 35.39 mL of NaOH(aq) is required to titrate 0.8246 g KHP to the equivalence point, what is the concentration of the NaOH(aq) ? (The molar mass of KHP = 204.2 g/mol) HC₈H₄O₄^-(aq) + OH^-(aq) $\leftrightharpoons$ C₈H₄O₄^2-(aq) + H₂O( $\ell$ )

A) 0.02318 M
B) 0.05705 M
C) 0.0859 M
D) 0.1141 M
E) 0.1429 M