What was the best-selling Beatles album?

Here is the question :

WHAT WAS THE BEST-SELLING BEATLES ALBUM?

Here is the option for the question :

Let It Be
Sgt. Pepper’s Lonely Hearts Club
Abbey Road
Help!

The Answer:

And, the answer for the the question is :

SGT. PEPPER’S LONELY HEARTS CLUB

Explanation:

[STC0013710]. With its 1967 release, The Beatles’ ‘Sgt. Pepper’s Lonely Hearts Club Band’ went on to sell over 32 million copies worldwide. Not only did it influence the development of pop music, but it also reimagined the band’s sound.