A: { name: "Lydia", age: 21 }

B: { name: "Lydia", age: 21, city: "Amsterdam" }

C: { name: "Lydia", age: 21, city: undefined }

D: "Amsterdam"

A: "Sorry, you're too young."

B: "Yay! You're old enough!"

C: ReferenceError

D: undefined

A: !!name

B: name

C: new Boolean(name)

D: name.length

A: """

B: "I"

C: SyntaxError

D: undefined

A: NaN

B: 20

C: ReferenceError

D: undefined

A: { default: function default(), name: "Lydia" }

B: { default: function default() }

C: { default: "Hello world", name: "Lydia" }

D: Global object of module.js

A: "class"

B: "function"

C: "object"

D: "string"

A: [1, 2, 3, 4, 5]

B: [1, 2, 3, 5]

C: [1, 2, 3, 4]

D: Error

A: name Lydia and age 21

B: ["name", "Lydia"] and ["age", 21]

C: ["name", "age"] and undefined

A: ["banana", "apple", "pear", "orange"]

B: [["banana", "apple"], "pear", "orange"]

C: ["banana", "apple", ["pear"], "orange"]

D: SyntaxError