S Block Elements

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R : Assertion (A) : $\mathrm{BeCl}_{2}$ and $\mathrm{MgCl}_{2}$ produce characteristic flame Reason (R) : The excitation energy is high in $\mathrm{BeCl}_{2}$ and $\mathrm{MgCl}_{2}$ In the light of the above statements, choose the correct answer from the options given below :