NYC is a type-in for New York City, which is frequently shortened to 'New York' in the answers. Since the state is also 'New York', unless the quiz's creator removes this type-in, NYC will also work for New York State.
Worth noting that the city's official name (and what JetPunk uses) is just New York. Since there's no way to tell whether the answer refers to the state or to the city, they went ahead and covered all the bases.