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Multiple ChoiceBeginner 30s

in Operator (MCQ)

Choose the best answer for: in keyword
Options
  1. 1The in operator checks whether a value exists in an array of items
  2. 2The in operator is the same as Array.includes for checking membership
  3. 3'prop' in obj checks property existence in object or prototype
  4. 4The in operator only works on arrays and never on plain objects
javascriptbeginner

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