For the hydrogen atom in the ground state, the energy levels of the electron are quantized. The energy of the first excited state of the hydrogen atom corresponds to 10.2 eV. This energy corresponds to the transition from the first excited state to the ground state.
Since the electron only makes a single transition from the first excited state to the ground state, there will be only one spectral line emitted.
Thus, the answer is Option (4): 1.