When a chinese company tried to purchase unocal, it was perceived by some in the u. s. as a. a threat to sovereignty. b. an avenue for illegal immigration. c. a drain on the economy. d. a potential devaluing of the dollar. e. a sign that the chinese economy was stronger than the u. s. economy.

The answer is A. threat to sovereignty.

Explanation:

Unocal is Union Oil company of California. This is an organization which is like a body , comprises of many oil companies. Taking over of this organization by a foreign company will be a threat to US. This is because, the board of directors, agents, group and affiliates of Unocal will be controlled by the owner. And this will be a threat to supreme power of authority in US.

cell regulation is conducted by special proteins.

the cost of mining is extremely low compared to the money earned from mining, creating income to improve the environment.