In a galvanic cell, electrons flow from

When in two container solutions of ZnSO₄ on the left side and CuSO₄ on the right side are placed and are connected through the external wire with battery and salt bridge the following reactions take place at the anode and cathode respectively.

As we know that an anode oxidation process takes place, here Zn electrode is the anode.At anode: Zn$\to$Zn⁺² + 2e^-
Zn²⁺ ions go into the solution and this Zn electrode occupies 2e^-, due to this occupation the Zn electrode becomes negatively charged. 
At the cathode reduction process is takes place, here Cu electrode is the cathode.
At cathode: Cu⁺² +2e^- $\to$Cu_(s)
The 2e^- electron which flows from the anode is gained by Cu solution and it is taken by Cu⁺² ions. This 2e^- are removed by Cu⁺² ions due to this Cu_(s) is accumulated by the copper electrode which positive polarity.
from the above process, it shows that electrons flow from anode to cathode in a galvanic cell.

Hence, the correct option is C).