IC the dc collector current of a BJT = 2 mA at room temperature

I_C the d_c collector current of a BJT = 2 mA at room temperature where kT/q = 25 m volts. Given h_fe = 100, the value of h_ie is given by—

Given, I_C = 2 mA,	kT	= 25 mV, h_ge = 100,
	q

we know that
β = g_m r_π (where β = h_fe = 100)

=		I_c	=	2 × 10^–3
		kT / q		25 × 10^–3

So, r_π = h_ie =		β	=	100	= 1250
		g_m		2 / 25

Hence alternative (C) is the correct answer.