ISRO | ISRO CS 2011 | Question 43
Which variable does not drive a terminal string in grammar?
S -> AB
A -> a
B -> b
B -> C
(A) A
(B) B
(C) C
(D) S
Answer: (C)
Explanation: C is the useless variable as there is no production rule which replaces C with a terminal. Hence it does not derive any non terminal.
Option (C) is correct.
Quiz of this Question