The quiescent collector current IC of a transistor is increased

The quiescent collector current I_C of a transistor is increased by changing the biasing resistance. As a result gm will—

1. Not be affected
2. Decrease
3. Increase
4. Increase or decrease depending on bias stability

As we know that

R₀ =	dV	,
	dI_C

on increasing quiescent collector current I_C, the output resistance R₀ decreases, as a result g_m.

g_m = g_m0			1		increases.
			R₀

Hence alternative (C) is the correct answer.