How can I make a random choice according to probabilities stored in a list (weighted random distribution)?

Given a list of probabilities like:

P = [0.10, 0.25, 0.60, 0.05]

(I can ensure that the sum of all the variables in P is always 1)

How can I write a function that randomly returns a valid index, according to the values in the list? In other words, for this specific input, I want it to return 0 10% of the time, 1 25% of the time, 2 60% of the time and 3 the remainind 5% of the time.