When the Oxidation-Reduction Reaction Shown Here Is Balanced Using the Smallest

Multiple Choice

When the oxidation-reduction reaction shown here is balanced using the smallest whole-number coefficients, how many electrons are transferred? Sn(s) +CL₂(g) $\rightarrow$ SnCL₄ (s)

A) 1
B) 2
C) 4
D) 8
E) 12