Which of the following statements best defines tides?
A. When waves gets bigger because of an approaching storm.
B. The rise of fall of ocean water that occurs about every 12.5 hours.
C. The rise of ocean water that occurs 12 times a day.
D. A giant wave that can be extremely dangerous without warning.
The statement that best defines tides is B. The rise or fall of ocean water that occurs about every 12.5 hours. Tides are the regular and predictable changes in the level of the ocean's surface. They are caused by the gravitational force of the Moon and, to a lesser extent, the Sun, acting upon the Earth's oceans. The gravitational pull of the Moon causes a bulge of water on the side of the Earth nearest to the Moon, creating a high tide. At the same time, there is a second bulge of water on the opposite side of the Earth, creating another high tide. In between these bulges, there are low tides. This process repeats approximately every 12.5 hours, resulting in two high tides and two low tides per day. So, option B is the most accurate description of tides.
