- Top-down parsers are LL parsers where first L stands for left – to – right scan and second L stands for a leftmost derivation.Correct
- (000)* is a regular expression that matches only strings containing an odd number of zeroes, including the empty string.Incorrect (000)* will generate ε, 000, 000000, 000000000, …….. multiples of 3 which include odd and even strings, so this is incorrect.
- Bottom-up parsers are in the LR family, where L stands for left – to – right scan and R stands for rightmost derivation.Correct
- The class of context – free languages is closed under reversal. That is, if L is any context – free language, then the language LR = {wR: w∈L} is context – free.Correct
So, option (B) is correct.