TANCET 2017 TOC

Question

Answer 1

Option 3.

S -> S1 | S2

S1 -> aS1S2c |⋋

S2 ->aS2b |⋋

S3 -> aS3B | S4 |⋋

S4 -> bS4c |⋋

k =|n-m|,satisfies in 3 option,

In other three options they reach to the S3 production which violates the Language ( it generates abcb string).