The correct answer is option 4, Pacific Ocean. The Pacific Ocean is the deepest ocean in the world. It has an average depth of about 12,080 feet (3,682 meters). The Pacific Ocean is also known for its deepest point, the Mariana Trench, which reaches a depth of 36,070 feet (10,972 meters).

Option 1, Atlantic Ocean, is not the correct answer as it is the second deepest ocean, with an average depth of about 12,080 feet (3,646 meters).

Option 2, Arctic Ocean, is not the correct answer as it is the shallowest ocean, with an average depth of about 3,366 feet (1,027 meters).

Option 3, Indian Ocean, is not the correct answer as it is the third deepest ocean, with an average depth of about 12,355 feet (3,766 meters).

Therefore, the Pacific Ocean is the deepest ocean in the world.