Which of the following is true ?
2020
Which of the following is true ?
- A.
Every subset of a regular set is regular
- B.
Every finite subset of non-regular set is regular
- C.
The union of two non-regular set is not regular
- D.
Infinite union of finite set is regular
Attempted by 57 students.
Show answer & explanation
Correct answer: B
The correct statement is that all finite languages are regular. This holds true regardless of the properties of any superset language. In contrast, subsets of regular languages can be non-regular (such as {a^n b^n | n ≥ 0}). Additionally, the union of two non-regular languages can be regular (for example, a language and its complement). Finally, infinite unions of finite sets do not guarantee regularity (e.g., {a^n b^n | n ≥ 0}).