String regex Quiz

What does the character class [a-z] represent in regex?

• Any lowercase letter from a to z

• Any number from 1 to 26

• Any uppercase letter from A to Z

• Any special character from a to z

Which quantifier in regex matches 0 or 1 occurrence of the preceding element?

• {}

• +

• ?

• *

Explain the use of grouping in regex with an example.

• Grouping in regex is used to remove special characters from a pattern.

• Grouping in regex is used to apply quantifiers to multiple characters, capture subpatterns, or create alternation. For example, (ab)+ will match one or more occurrences of 'ab'.

• Grouping in regex is used to change the order of characters in a pattern.

• Grouping in regex is used to match any character in a pattern.

What is the purpose of using the character class [0-9] in regex?

• To match any single digit from 1 to 9

• To match any special character

• To match any single letter from a to z

• To match any single digit from 0 to 9.

Which quantifier in regex matches 0 or more occurrences of the preceding element?

• ?

• +

• !

• *

How can you use grouping to capture a specific part of a string in regex?

• By using curly braces {} to create a capturing group

• By using parentheses () to create a capturing group

• By using angle brackets <> to create a capturing group

• By using square brackets [] to create a capturing group

Explain the difference between the character classes [A-Z] and [a-z] in regex.

• [A-Z] matches uppercase letters and [a-z] matches lowercase letters.

• [A-Z] matches lowercase letters and [a-z] matches uppercase letters.

• [A-Z] matches numbers and [a-z] matches special characters.

• [A-Z] matches vowels and [a-z] matches consonants.

What is the significance of using the character class [^] in regex?

• It matches any character including the ones listed

• It only matches the first character in the list

• It matches any character except for special characters

• It matches any character except the ones listed

How can you use character classes to match any alphanumeric character in regex?

• [a-zA-Z]

• [A-Z0-9]

• [a-z0-9]

• [a-zA-Z0-9]