The decay constants of a radioactive substance for $$\alpha$$ and $$\beta$$ emission are $$\lambda_\alpha$$ and $$\lambda_\beta$$ respectively. If the substance emits $$\alpha$$ and $$\beta$$ simultaneously, then the average half life of the material will be

A

$$\frac{2T_\alpha T_\beta}{T_\alpha + T_\beta}$$

B

$$T_\alpha + T_\beta$$

C

$$\frac{T_\alpha T_\beta}{T_\alpha + T_\beta}$$

D

$$\frac{1}{2}(T_\alpha + T_\beta)$$