Balance the Following Redox Reaction Under Basic Aqueous Conditions Using $\rightarrow$

Multiple Choice

Balance the following redox reaction under basic aqueous conditions using the smallest whole-number coefficients possible.What is the coefficient of ClO₃^-?
ClO₃ ^- (aq) +S₂O₃^{2 -} (aq) $\rightarrow$ Cl₂ (aq) +SO₃^2-(aq)

A) 2
B) 3
C) 4
D) 5
E) 6