The reaction of zinc with copper sulfate solution is: 

Zinc will take the place of copper from the copper sulphate solution in the interaction between zinc and copper sulphate. Now, you can only select the right response if you understand how to balance this reaction.

When zinc is added to copper sulphate solution, zinc generates zinc sulphate solution by displacing copper from copper sulphate. Because zinc is more reactive than copper in the reactivity series, it will go through a redox process known as the displacement reaction of metal.
However, as copper is a transition metal with a range of oxidation states, it first relies on what that state is. Copper (I), Copper (II), and even Copper are all available (III). Additionally, for the reaction to take place, the copper sulphate has to be in an aqueous condition, or dissolved in water.

Since zinc is more reactive than copper and displaces less reactive metal from its solution when added to ${\mathrm{CuSO}}_4$ solution, zinc displaces copper from copper sulphate and forms zinc sulphate solution.
The colour switches from blue to colourless to show this.
While ${\mathrm{ZnSO}}_4$ solution is colourless, ${\mathrm{CuSO}}_4$ solution is blue.

The following reaction takes place; $\mathrm{Zn}+{\mathrm{CuSO}}_4\to {\mathrm{ZnSO}}_4+\mathrm{Cu}$

Hence, option C is correct.