Electrostatics Cavity problem(JEE ADVANCED 2015)

Consider a uniform spherical charge distribution of radius R₁ centred at the origin O. In this distribution, a spherical cavity of radius R2, centred at P with distance OP = a = R1 R2 (see figure) is made. If the electric field inside the cavity at position r is E(r), then the correct statement(s) is (are):-

[@Ride_with_Super_Human]

Supercalifragilisticexpealudicious sir!

[@Squid_suraj]

Nice explanation ❤❤❤