Which class is used to represent a group of characters in a regular expression in Java?

What is a regular expression in Java?

A. A pattern that describes a set of strings

B. A Java class for reading regular expressions

C. A Java method for creating strings

D. A Java package for file operations

Which class is used to compile a regular expression in Java?

A. `String`

B. `Regex`

C. `Matcher`

D. `Pattern`

In a regular expression, what does the metacharacter `.` represent?

A. A digit

B. A space

C. Any character

D. A word

What does the character class `[A-Za-z]` match in a regular expression?

A. Any special character

B. Any uppercase or lowercase letter

C. Any whitespace character

D. None of These