1. What is the purpose of a constructor in a JavaScript class?
A) To initialize object properties
B) To define methods
C) To inherit properties
D) To create static methods
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2. How do you access properties of an object using the `this` keyword?
A) Using the object's name
B) Using 'this.propertyName'
C) Using 'self.propertyName'
D) Using 'current.propertyName'
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3. What does the `super` keyword do in a derived class?
A) It creates a new instance
B) It calls the parent class constructor
C) It defines a new method
D) It accesses private properties
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4. Which of the following is a correct way to create a regular expression in JavaScript?
A) /abc/
B) new RegExp('abc')
C) 'abc'
D) Both A and B
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5. What method would you use to test if a string contains a specific pattern using regex?
A) match()
B) search()
C) test()
D) find()
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6. How do you replace a substring in a string using a regular expression?
A) replaceAll()
B) replace()
C) substitute()
D) modify()
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7. What does the regex pattern `/\d+/` match?
A) One or more digits
B) One or more letters
C) One or more whitespace characters
D) A single character
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8. Which method returns an array of matches when using a regular expression?
A) test()
B) match()
C) search()
D) replace()
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9. What does the `g` flag in a regex pattern do?
A) Matches only the first occurrence
B) Ignores case sensitivity
C) Allows matching all occurrences
D) Restricts matches to a specific range
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10. Which character is used to denote the start of a line in a regex pattern?
A) $
B) *
C) .
D) ^
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11. What will `instanceof` return if an object is an instance of a class?
A) true
B) false
C) null
D) undefined
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12. Which keyword is used to create a new class in JavaScript?
A) define
B) class
C) function
D) new
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13. What is a method in a JavaScript class?
A) A function defined in a class
B) A variable defined in a class
C) A property of an object
D) A keyword in JavaScript
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14. What does the regex pattern `/^a/` match?
A) Any string that starts with 'a'
B) Any string that ends with 'a'
C) Any string that contains 'a'
D) An empty string
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15. Which regex pattern would match any character except a newline?
A) .
B) \n
C) \s
D) ^
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16. What does the `i` flag do in a regex pattern?
A) Makes the pattern case-insensitive
B) Matches only lowercase letters
C) Matches only uppercase letters
D) Ignores whitespace characters
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17. How do you match one or more whitespace characters in a regex pattern?
A) \s
B) \s*
C) \s+
D) \w+
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18. Which method can be used to check if a string matches a regex pattern?
A) test()
B) match()
C) search()
D) replace()
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19. What does the regex pattern `/[a-z]/` match?
A) Any lowercase letter
B) Any uppercase letter
C) Any digit
D) Any special character
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20. How do you escape a special character in a regex pattern?
A) Use a backslash (\)
B) Use a forward slash (/)
C) Use a caret (^)
D) Use a period (.)
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