Which of the following are major ocean gyres?

The North Pacific is indeed one of the major ocean gyres. Ocean gyres are large systems of rotating ocean currents, primarily driven by the wind patterns and the Earth's rotation. The North Pacific gyre, specifically, is characterized by its expansive area that influences climate patterns and marine biodiversity across the Pacific Ocean.

Each gyre typically contains distinct regions of warm and cold water currents, which play a crucial role in regulating sea temperatures and weather patterns across broader areas. In the case of the North Pacific, it interacts with other significant oceanic features, including the California Current and the Alaska Current, which further contribute to its importance in oceanographic studies.

The other choices represent important oceanic features as well, but they are not classified as major gyres in the context of the classical definitions. The North Atlantic gyre is another well-known major gyre and warrants recognition, while the South Indian and South Pacific involve current systems that are significant but do not hold the same status as the major gyres such as the North Pacific and North Atlantic. Understanding these major gyres is important for navigation, weather prediction, and ecological studies in the oceans.