Answer:
It would have an inductance closest to 16 L.
Step-by-step explanation:
Inductance for a one solenoid can be calculated with a formula following:
L=μ*N^2*A/l
Then, in this situation we are increasing the number of turns by 4 without any length change. First solenoid with 50 turn has inductance L which is:
L= μ*50^2*A/l=2500*μ*A/l
When we increase the number of turns by four, it will increase to:
L'=μ*200^2*A/l=40000*μ*A/l=16 L