An electron is travelling with a velocity $$v$$ in free space and when it enters a medium, its velocity is reduced by 20%. The de Broglie wavelength of electron in the medium is $$\alpha \lambda_0$$.where $$\lambda_0$$ is its de Broglie wavelength in free space. The value of $$\alpha$$ is :

A

$$1.20$$

B

$$1.0$$

C

$$1.25$$

D

$$0.75$$