Most U. S. beaches are shrinking or encroaching on the land rather than growing or moving seaward, so the land of the U. S. is getting smaller, not bigger. Which of the following is a likely cause for loss of at least some of our beaches: Group of answer choices

a. Sea-level rise as the last ice age
b. drained river valleys to destroy bays,
c. so sediment now is taken to the coast to feed beaches rather than being trapped in bays.