The correct answer is option 3 - The Crux.

In the southern hemisphere, navigators used The Crux, also known as the Southern Cross, to find their directions in the high seas. The Crux is a prominent and easily recognizable group of stars that form a cross-like shape. It consists of four bright stars, and it is one of the most famous constellations visible from the southern hemisphere.

Option 1 - The Crion is incorrect. There is no such group of stars known as The Crion that is used for navigation in the southern hemisphere.

Option 2 - The Polaris is incorrect. Polaris, also known as the North Star, is used for navigation in the northern hemisphere, not in the southern hemisphere.

Option 4 - The Great Bear is incorrect. The Great Bear, also known as Ursa Major, is a constellation used for navigation in the northern hemisphere, not in the southern hemisphere.

Overall, The Crux is the correct answer as it is the constellation used by navigators in the southern hemisphere to find their directions in the high seas.