B because they study the importance of people and environments and the changes in these enviroments
North Korea?
I'm a math guy, not sure about it.
The correct statement is: Increased immigration has led to an improved competitive edge in the global market.
The increased immigration has led to more people with the same, or different skills to be competing on the global market, which led to a higher quality work and increased competitiveness.
The increased competition on the market is always a push factor towards an improvement in the job skills in the people competing for the jobs, as they have to be better than the others in order to get the job. Also, because there are lot of skillful workers that are always on the market, the ones that are employed are giving their best to be consistent, productive, and upgrade, in order to keep their jobs.
