While true, that would be non-euclidean chocolate, you cannot have a 1 dimension physical object.

I'm not sure I understand; why would fizzBuzz[1] be undefined?

Not to be overly pedantic, but (123) is not a valid area code, 0 and 1 are reserved first digits, both in 10 and 7 digit phone numbers.

The examples in the description show fizzBuzz as an array, not a function. They say to check for fizzBuzz[n], not fizzBuzz()[n].

The example in the description is not similar to what the test cases would be, nor are there any pre-submission test cases.

fizzBuzz[1] would be undefined, fizzBuzz()[x] or fizzBuzz = fizzBuzz(); would work, but that's not made obvious in the example.