If $n_h$ is the number of holes per unit volume and $n_e$ is the number of conduction electrons per unit volume in an extrinsic semiconductor. The relation between $n_h, n_e$ and $n_i$ is ($n_i$, is intrinsic carrier concentration)

$n_i^2 = n_en_h$ $n_i = n_en_h$ $n_e=n_h$ $n_i^2 > n_en_h$

$n_i^2 = n_en_h$

The correct answer is Option (1) → $n_i^2 = n_en_h$