Final answer:
Cape Town, Buenos Aires, and Montevideo are the cities that should be labeled as they are located south of 30 degrees north latitude and west of 15 degrees east longitude. Windhoek does not meet the geographic criteria.
Step-by-step explanation:
The question asks to label the cities located south of 30 degrees north latitude and west of 15 degrees east longitude. According to the given coordinates, we can determine which cities among Cape Town, Buenos Aires, Montevideo and Windhoek meet the criteria.
- Buenos Aires and Montevideo are both in the Southern Cone region of South America, which lies south of the Tropic of Capricorn and is indeed south of 30 degrees north latitude and west of 15 degrees east longitude.
- Cape Town is located at the southern tip of Africa and also meets the criteria of being south of the Tropic of Capricorn.
- Windhoek, although in southern Africa, is north of the Tropic of Capricorn and does not meet the geographic criteria.
Therefore, the cities that should be labeled according to the specified latitude and longitude are Cape Town, Buenos Aires, and Montevideo.