Which function is used to find unique elements in an array in Underscore.js?

What does _.keys({one: 1, two: 2, three: 3}) return?

A). [1, 2, 3]

B). ['one', 'two', 'three']

C). ['1', '2', '3']

D). [1, 2, 'three']

What does _.identity(value) return?

A). null

B). undefined

C). The same value

D). A new value

How do you flatten a nested array using Underscore.js?

A). _.map

B). _.flatten

C). _.filter

D). _.reduce

How do you shuffle the elements of an array in Underscore.js?

A). _.each

B). _.shuffle

C). _.sample

D). _.random

How do you debounce a function in Underscore.js to limit the rate at which it can fire?

A). _.throttle

B). _.debounce

C). _.delay

D). _.once

What is the output of _.last([1, 2, 3, 4, 5], 2)?

A). [1, 2]

B). [4, 5]

C). [5]

D). [3, 4, 5]

What does _.omit({name: 'Alice', age: 25, location: 'NY'}, 'age') return?

A). {name: 'Alice', location: 'NY'}

B). {age: 25}

C). {name: 'Alice', age: 25}

D). {location: 'NY'}

What is the result of _.map([1, 2, 3], function(num) { return num * 3; })?

A). [1, 2, 3]

B). [3, 6, 9]

C). [2, 4, 6]

D). [3, 6, 9, 12]

What is the result of _.reduce([1, 2, 3], function(sum, num) { return sum + num; }, 0)?

A). 6

B). 5

C). 3

D). 2

What does the _.each function do in Underscore.js?

A). Iterates over a list of elements

B). Creates a new array with transformed values

C). Filters values in a list

D). Reduces the list to a single value