Question

which action causes breakers?
waves hit the shore at an angle and transport sand.
water flows away from the shore and moves sand with it.
underwater earthquakes cause motion throughout ocean water.
waves meet the shore and cause the crest to spill over the trough.

Explanation:

Breakers are formed when waves approach the shore. As the wave moves into shallower water, the bottom of the wave slows down due to friction with the seabed. The top of the wave (crest) continues moving forward at a relatively faster speed. Eventually, the crest becomes unstable and spills over the trough, creating a breaker.

• The first option describes long - shore drift (waves hitting at an angle and transporting sand), not breaker formation.
• The second option is about backwash (water flowing away from the shore), not breaker formation.
• The third option is about tsunamis (caused by underwater earthquakes), not breakers.

Answer:

Waves meet the shore and cause the crest to spill over the trough.