What is the purpose of the 'super' keyword in a ...
A). It calls methods from the paren...
B). It creates a new instance of the...
C). It refers to the current object.
D). It checks for property existence.
What does Object.keys(obj) return?
A). An array of object keys.
B). An array of object values.
C). An array of object properties.
D). An array of object methods.
How do you add a new property 'age' with value 25...
A). person.age = 25;
B). person['age'] = 25;
C). person.add('age', 25);
D). person.push('age', 25);
What will console.log(obj.toString()) output?
A). The string representation of...
B). The object itself.
C). An error.
D). 1
What does the Object.values(obj) method return?
A). An array of object keys.
B). An array of object values.
C). An array of object properties.
D). An array of object methods.
How do you define a method 'sayHello' in an obj...
A). person.sayHello = function() {};
B). person.sayHello: function() {};
C). person.sayHello = () {};
D). person.sayHello = function {};
How do you access nested properties in an object?
A). obj.property.nestedProp (B21)
B). obj['property']['nestedProp'] (C21)
C). obj.property['nestedProp'] (D21)
D). obj['property'].nestedProp (E21)
What is the output of console.log(obj.prop) if ob...
A). It prints undefined.
B). It throws an error.
C). It prints null.
D). It prints true.
How do you check if an object has a property 'col...
A). 'color' in obj
B). obj.hasProperty('color');
C). obj.contains('color');
D). obj.propertyExists('color');
How do you get the number of properties in an obj...
A). Object.keys(book).length
B). book.countProperties()
C). book.totalProperties()
D). book.length()