In some programming languages, an identifier is permitted to be a letter followed by any number of letters or digits. If L and D denotes the set of letters and digit respectively. Which of the following expression defines an identifier?
A)(L + D) *
B)(L.D) *
C)L(L + D) *
D)L(L.D) *

Question

Quizplus · Accepted Answer

Option C, L(L + D)*, correctly defines an identifier that starts with a letter followed by any number of letters or digits. The first L ensures the identifier starts with a letter, and (L + D)* allows for any combination of letters and digits thereafter, including none.

In Some Programming Languages, an Identifier Is Permitted to Be