Which is an important issue the united states faces in the twenty-first century?

terrorism

global warming

globalization

all of the above

The correct answer is D. All of the above

Explanation:

The twenty-first century implied multiple changes for all the countries around the world including the U.S. these changes are related to the use of technology, the globalization, international relationships, overpopulation among others that represent issues and challenges for the U.S.

Particularly during the two last decades, the U.S. has experienced issues related to terrorism that began with the attacks that occur on September 11th of 2001 as an Islamic terrorist group attacked different buildings in the U.S. as well as subsequent attacks. Besides this, globalization and relationship with other countries have become an issue for the U.S. especially as globalization allows the flow of technology and people, but it is also a challenge in terms of economy and identity. Finally, overpopulation and global warming linked to industrialization is also an issue for the United States as there are already multiple effects of global warming and despite different actions, temperatures keep increasing. Therefore, all of the above (terrorist, global warming and globalization) are important issues the U.S. face in the twenty-first century.

a. competition with other nations.

ok sorry the answer is a. by their religion