I don't want to alarm you. There is

I don't want to alarm you. There is still enough sand left in the world to satisfy most holidaymakers but in many parts of the world beaches are literally being (1)____________ away and have to be regularly (2)____________.
First, much of the sand for beaches (3)____________ from cliffs which crumble away as they are pounded by the waves. To (4)____________ them, sea walls are often erected. With cliffs no (5)____________ crumbling, the beaches are robbed of the material which would (6)____________ feed them.
Beaches are also (7)____________ with sand and gravel by rivers which bring it down from the mountains and hills. In some places rivers are being dammed and (8)____________ built to retain water. They trap more of the sediment so the rivers (9)____________ less sand and gravel to the sea. This is happening in California, for example, and in Scotland. In Egypt the (10)____________ of the Aswan Dam has (11)____________ the Nile silt, so much less silt is being fed towards coastal (12)____________. That has meant the delta is now eroding instead of (13) as before.
Thirdly, to improve access to the beach many holiday resorts build a promenade along the sea front. Like some of the fortifications of cliff (14)____________, this usually has a flat vertical surface off which the waves (15)____________. This helps wash the sand away down the beach and most of it is lost.

Choose the best answer to fill in the blank

1. a. thrown b. rubbed c. washed d. cleaned
2. a. removed b. replaced c. rebuilt d. redrawn
3. a. collects b. forms c. falls d. comes
4. a. protect b. prepare c.surround d. cover
5. a. sooner b. longer c. further d.later
6 a. normally b. often c. sometimes d. occasionally
7. a. presented b. given c. filled d. supplied
8. a. reservoirs b. canals c. wells d. locks
9. a.fetch b.take c. pull d. push
10. a. designing b. engineering c. building d. forming
11. a. kept b. trapped c.sealed d.solidified
12. a. beaches b. resorts c.areas d.parts
13. a.growing b.shrinking c.swelling d.reducing
14. a.tops b. faces c.features d.hangings
15. a.bounce b.jump c.splash d. ripple