Which is the correct method to show that zinc is more reactive than copper 

If we dissolve or dip the zinc metal granules in the aqueous copper sulphate solution, after waiting for one or two hour time period then we can observe that zinc is completely displaced copper.

$\text{Zn}\left(\text{s}\right)+{\text{\hspace{0.17em}\hspace{0.17em}CuSO}}_{\text{4}}\left(\text{aq}\right)\to \text{\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}Cu}\left(\text{s}\right)+{\text{\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}ZnSO}}_{\text{4}}\left(\text{aq}\right)$