Identify the Acid in the Following Acid-Base Reaction:
3 $\rightarrow$

Identify the acid in the following acid-base reaction:
3 NaHSO₄ (aq) + Fe(OH) ₃ (s) $\rightarrow$ Fe ³⁺(aq) +3 SO₄^2-(aq) + 3 Na⁺(aq) +3 H₂O(l)

A) HSO₄-
B) Na⁺
C) Fe³⁺
D) OH^-
E) SO₄^{2 -}