Electrostatics Part 2

The given situation is shown below There can be two cases here
Case 1 Considering the outer spherical shell as non-conducting.So, electric field for any point with r < R
Einside=0 and for
r>R,E=

kQ

r2

In this case, option (b) is correct.
Case 2 Considering the outer spherical shell as conducting. Now,charge will be induced on it.r<R,E=0
R≤r<a,E=

kQ

r2

a≤r<b,E=0
r≥b,E=

kQ

r2

In this case, option (a) is correct.