Which of the following correctly represents the definition of a regular…
2025
Which of the following correctly represents the definition of a regular expression over the alphabet {a, b}?
Answer: A. A symbolic representation used to define a language that can be accepted by a finite automaton — A regular expression is a symbolic notation used to describe patterns in strings, specifically defining the set of all strings that belong to a regular…
- A.
A symbolic representation used to define a language that can be accepted by a finite automaton
- B.
A finite set of rules used to compute numeric functions recursively
- C.
A diagrammatic technique to model context-free grammars
- D.
A tree-based structure used to analyze semantic meaning in programming languages
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Correct answer: A
A regular expression is a symbolic notation used to describe patterns in strings, specifically defining the set of all strings that belong to a regular language. In formal language theory, there is a fundamental equivalence between regular expressions and finite automata: every regular expression can be converted into an equivalent finite automaton (like a DFA or NFA) that accepts exactly the same language, and vice versa.
Therefore, Option A is correct because it accurately captures this relationship by defining regular expressions as symbolic representations for languages accepted by finite automata.
Option B is incorrect because it describes recursive functions, which relate to computability theory rather than pattern matching.
Option C is wrong as it refers to parsing techniques for context-free grammars, which are more powerful than regular languages.
Option D describes abstract syntax trees used in compiler semantics, not pattern definitions.