What was the pattern of mongol settlement in russia?

the mongols only built up cities with existing churches.
the mongols built new cities in russia.
the mongols only built up russian cities that were deemed vitally important.
the mongols built up all russian cities.

Read this passage: wendy is trying to learn more about the city's role in a chemical spill that occurred a few miles from her apartment. when she finds only a very short article in the local newspaper, she searches for articles on larger newspapers' websites to determine what might have been left out of the original article. which method of identifying bias is most clearly used in the passage? a. considering motivations for bias b. using a variety of media sources for information c. fact-checking stories d. comparing different stories on the same topic