Given the question: Answer the following question given this paragraph: Only a tiny fraction of the ocean floor has ever been studied. Why? Humans can't travel deep below the water's surface without special vehicles. The pressure of the water is too great. Total darkness and extreme cold make it even more difficult. That's why people have worked for decades to invent technology for studying the ocean floor. Q: What is the name of artificial barriers that people build to protect shorelines? Choices: - seawalls - domes - outcroppings - breakwaters A:
The answer is:
breakwaters