GKFix MCQ Question

What is the second ionization reaction of a dibasic acid HX–?

• A. HX– ⇌ 2H+ + X^2–
• B. HX– ⇌ H+ + X^2–
• C. HX– ⇌ H2 + X
• D. HX– ⇌ H+ + H2X