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

Answer & Solution

Answer: Option B
Solution:
The _.keys function retrieves all the names of the object's properties.
Related Questions on Average

Which function is used to clone an object in Underscore.js?

A). _.extend

B). _.clone

C). _.map

D). _.filter

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

A). _.each

B). _.shuffle

C). _.sample

D). _.random

How do you extend an object with properties from other objects in Underscore.js?

A). _.clone

B). _.extend

C). _.omit

D). _.pick

What does _.pluck([{a: 1}, {a: 2}, {a: 3}], 'a') return?

A). [1, 2, 3]

B). [1, 2]

C). [2, 3]

D). [3, 1]

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 _.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'}

Which function can be used to delay the execution of a function in Underscore.js?

A). _.defer

B). _.delay

C). _.debounce

D). _.throttle

What does the _.filter 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

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

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

A). [1, 2]

B). [4, 5]

C). [5]

D). [3, 4, 5]