Correct Answer - Option 2 : 2 kΩ

**Concept:**

The output Resistance of FET is defined as

\({r_o} = \frac{1}{{\lambda {I_D}}}\)

Where λ = channel length modulator parameter

I_{D} = drain current

**Calculation:**

Given

λ = 0.05 V^{-1}

I_{D} = 10 mA Important Point:

\({r_o} = \frac{1}{{\lambda {I_D}}} = \frac{1}{{0.05 \times 10 \times {{10}^{ - 3}}}} = 2K{\rm{\Omega }}\)

**NOTE: **

If MOSFET does not have a channel length modulator then ⇒** λ = 0**

\({r_{ds}} = \frac{1}{{\lambda {I_{DS}}}} = \infty \) (of P resistance)