How does the index after the random.choices exactly work?

I have a list:

background = ["blue", "green", "pink", "purple", "yellow"]

And there are two "versions" of random.choices I tried (one indexing something and the other not indexing something)

choice = random.choices(background)

And the other one:

choice - random.choices(background)[0]

The output of version one is, for example:

["blue"]

And version two:

blue

My question here is, how exactly does the indexing in this example work? Wouldn't an index of [1] give you the output of b or l ?