The ratio of total energy to the kinetic energy of an electron in a Bohr orbit of the hydrogen atom is

-1 : 1

The correct answer is Option (3) → -1 : 1

In Bohr model:

Kinetic energy of electron: $K = -E$

Total energy of electron: $E = -K$

Potential energy: $U = 2E = -2K$

Therefore, $\frac{E}{K} = \frac{-K}{K} = -1$

Answer: The ratio of total energy to kinetic energy is $-1$.