Answer:
D: communities that use the latest digital technology, particularly computer systems that respond to input from networks of sensors, to deliver city services efficiently and improve urban life
Explanation:
This links back to the main idea of the passage and the writer wants a sentence in order "to help clarify the central concept of the essay."
D. A farewell urging the listener not to be sad.
A valediction is a goodbye statement. Forbidding mourning is saying to not be upset or sad.
<span>Eric the Red left Norway and founded a settlement in Greenland and then he had a son. He was oon off course and he finally landed in a strange land and historian may believe he have been in USA or Canada
Hope this helps</span>
