Final answer:
The movie 'Yellow Submarine' was successful due to its unique animation style, catchy soundtrack, and compelling storyline.
Step-by-step explanation:
The movie 'Yellow Submarine' was successful for several reasons. One reason is its unique animation style, which was visually appealing and different from other animated films at the time. Another factor is the catchy soundtrack, featuring popular songs from The Beatles, such as 'Help!' and 'Let It Be.' Lastly, the movie had a compelling storyline that captivated audiences, making them emotionally invested in the characters and their journey.