It is a dumb question because you do not select a Mosfet's threshold voltage, you get whatever they have. The threshold voltage for most Mosfets is when its drain current is only 0.25mA so it is almost turned off. With a 4k drain resistor than I think the drain current will be 1mA.
Surely Id is > 1 mA because Vgs@1mA < Vgs@4mA. You need to solve a quadratic equation to get the exact value.
Like most exercise problems, it's not about designing with real MOSFET, type variations etc. Just assuming Vth of exactly 2V and an ideal quadratic characteristic.