As an electron makes a transition from an excited state to the ground state of a hydrogen - like atom/ ion :

Question

$\begin{array}{1 1} \text{kinetic energy, potential energy and total energy decrease } \\ \text{kinetic energy decreases, potential energy increases but total energy remains same} \\ \text{kinetic energy and total energy decreases but potential energy increases } \\ \text{its kinetic energy increases but potential energy and total energy decreases } \end{array} $