If the current through a galvanometer is I=kθ/NAB, then what is the sensitivity of the galvanometer?

Question : If the current through a galvanometer is I=kθ/NAB, then what is the sensitivity of the galvanometer?

a)NAB/k
b)k/NAB
c)NAB/kθ
d) None of the above.

Doubt by Tanya

Solution : 

We know 

Current sensitivity (IS) = 
θ/I 
I=kθ/NAB
NAB/k=
θ/I
θ/I=NAB/k
Current Sensitivity (IS) = 
NAB/k

Hence, a)NAB/k is correct.