How many high tides and low tides occur each day

The correct answer is - two high tides and two low tides.

The high tides and the low tides occur because of the effect of the gravitational pull of the Moon on the water bodies on the Earth. The gravitational pull from the Moon is pulling the waters toward it, resulting in moving of the water from the sides of the planet (compared to the position of the Moon) toward the side where the Moon is, and on the total opposite side of the planet. The high tide occurs when the gravitational pull of the Moon is the strongest, and it occurs on both sides of the planet, the two total opposite places, while in the same time, the sides of the planet experience low tides. As the Moon moves around the Earth, when it reaches the total opposite sides, it causes another high tide and low tide on the same places, resulting in two high tides, and two low tides during a single day.