Ahunter illegally kills a wolf in yellowstone national park and attempts to bring the wolf's skull back to florida. which law is the hunter violating?

The hunter is violating the Lacey Act

The Lacey Act is a conservation law that was introduced in the United States to stop the transportation of illegally captured animals or wildlife products. This law enforces criminal and civil penalties for people that are found guilty of selling, purchasing or receiving illegal forest products.

the answer to your question is:

c. complementary base-pairing

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.