Assertion: For a cell reaction\[Zn(s)+C{{u}^{2+}}(aq)\to \] \[Z{{n}^{2+}}(aq)+Cu(s)\]; at the equilibrium, voltmeter gives zero reading. Reason: At the equilibrium, there is no change in the concentration of \[C{{u}^{2+}}\]and \[Z{{n}^{2+}}\] ions. Read the assertion and reason carefully to mark the correct option out of the options given below:

• A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
• B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
• C. If assertion is true but reason is false.
• D. If the assertion and reason both are false.
• E. If assertion is false but reason is true.