What is the data type of a constant object in JavaScript?
A). A. Object
B). B. Array
C). C. Function
D). D. String
What happens if you use Object.freeze() on a constant object in JavaScript?
A). A. The object reference becomes mutable
B). B. The properties of the object become immutable
C). C. The object becomes frozen and cannot be modified
D). D. A TypeError is thrown
What is the result of the expression Object.keys(person).length for the following code snippet?
A). A. 1
B). B. 2
C). C. 3
D). D. Error
What does the const keyword do when used to declare an object in JavaScript?
A). A. Makes the object immutable
B). B. Prevents reassignment of the object reference
C). C. Freezes all properties of the object
D). D. All of the above
How can you prevent modifications to the properties of a JavaScript object?
A). A. Use Object.preventExtensions()
B). B. Use const for each property
C). C. Use Object.freeze() to freeze the object
D). D. All of the above
Which of the following will cause an error when used with a constant object in JavaScript?
A). A. Modifying a property using bracket notation
B). B. Adding a property using dot notation
C). C. Deleting a property
D). D. Reassigning the object reference
How can you check if an object is frozen in JavaScript?
A). A. Using the frozen property
B). B. Using the isFrozen() method
C). C. Using the Object.isFrozen() method
D). D. All of the above
Which statement is true about constant objects in JavaScript?
A). A. The properties of a constant object cannot be changed
B). B. Constant objects are frozen and immutable
C). C. Constant objects cannot have properties added or deleted
D). D. The object reference can be reassigned
Which of the following is a valid way to define a constant object in JavaScript?
A). A. const obj = { a: 1, b: 2 };
B). B. const obj = new Object({ a: 1, b: 2 });
C). C. Both A and B
D). D. None of the above
What is the correct way to modify a property of a constant object in JavaScript?
A). A. Use the delete keyword
B). B. Use the const keyword for the property
C). C. Use dot notation or bracket notation to access and modify the property
D). D. Use Object.freeze() to freeze the object