Assertion If we consider system of two bodies `A and B` as a whole, `F_(AB) and F_(BA)` are internal forces of the system `(A + B)`. They add to give a null force.
Reason: Internal forces in a body or a system of particles cancel away in pairs.
Options:
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false and R is also false.