Do you have the answer choices?
Secondary sources draw on primary sources. They may comment on primary sources, or use the evidence from primary sources to construct an argument. Books or journal articles that analyze, critique, or synthesize a range of sources are examples of secondary sources.
?????????????????????????????????????? IT"S A WHO HOO
China--Nixon recognized Communist China and was the first president to visit the country. He also began trade talks regarding China.
Vietnam--Nixon pulled out ground troops and created a peace agreement to end US involvement in Vietnam.
Nixon created the EPA which provided federal funding to protect the environment and create industry regulations on companies.
The hydrological structure of the drainage basin is a localized open system. A drainage basin is a piece of land that is drained by a river and its tributary.
<h3>What are the disadvantages of this system?</h3>
Basin irrigation is the most frequent type of surface irrigation, particularly in areas with modest field layouts.
Disadvantages of Basin Irrigation System:
1. It is not applicable to all crops.
2. There is water waste in it.
3. Diseases propagate through trees.
Thus Option A is the correct option.
For more information about Basin Irrigation system refer to the link:
brainly.com/question/1152007