Answer: Python Puzzler #3770

The answer is B. The program prints:

meow

This answer was checked by running the program for real.

Why?

A dictionary stores pairs: a key and its value. sounds["cat"] looks up the key ‘cat’ and gives back its value.

Trace table

A trace table follows the program step by step. Here’s this one:

key	value
cow	moo
cat	meow
sheep	baa
dog	woof

The code again

sounds = {
    "cow": "moo",
    "cat": "meow",
    "sheep": "baa",
    "dog": "woof",
}
print(sounds["cat"])