S ---> S1,S1---> abS1,S1---> ab, S ---> S2, S2—> baS2, S2—> ba

S ---> S1,Sl ---> aS1,S1---> ab, S ---> S2, S2---> bS2, S2 —> bc

S —> S1,S1—>S2, S2—>S1a,S1—> ab, S2—> ba

none of these

n²

n + 1

2n

2n - 1

Type 0

Type 1

Type 2

Type 3

202021

1202020

1020202

none of these

Recursive language is recursive

Recursively enumerable language is recursively enumerable

Recursive language is either recursive or recursively enumerable

None of these