You have an analyte solution of 50 mL of 0.2 M acetic acid (pK_a = 4.8). What volume of 0.05 M NaOH titrant needs to be added to get the final pH = pK_a?

• A. 20 mL
• B. 50 mL
• C. 100 mL
• D. 150 mL