I have a question about a practice test!! Why is the correct answer A? I chose B. I don't know the difference between A and B.

Question

Both in Egypt and Mesopotamia, the periodic floods of great rivers such as the Nile and the Tigris-Euphrates not only supplied water to the fields but also brought down fresh soil in the form of fertile muddy sediments. This sediment was deposited on flood plains around such rivers, thus annually restoring the fruitfulness of the land. This regular flooding and sediment deposit allowed these early farmers to continue cultivating the same fields repeatedly for generations without exhausting the fertility of the soil, and crop surpluses were, therefore, available to allow an increase in population and a growth in trade and skills development. The area available for cultivation was expanded when people learned to draw off the river water into man-made irrigation canals and ditches, watering and fertilizing larger and larger areas of land.

 

According to paragraph 4, why did early Neolithic people build irrigation ditches?

 

A. To increase the growing areas

 

B. To enlarge the fertilized areas

 

C. To produce crop surpluses

 

D. To water the early canals

 

Answer 1

Hi Saori,

 

      Please read the last sentence of the paragraph carefully. It talks about expansion of the area available for cultivation through construction of irrigation canals  and ditches by people. Such construction did not increase already fertilized area as stated in B; it created new growing areas though added water supply and increased the total growing area as stated in A. Therefore, A is correct and B is not.

 

     People did not know if ditches would produce extra crop and therefore, C is incorrect.

 

     Similarly, there is no indication about existence of early canals and therefore, D is incorrect.

 

      Hope it helps.