Different evolutionary lines that encounter extremely similar forces of natural election tend to become more similar as they evolve. This is known as

convergent evolution

Explanation:

Convergent evolution is the evolutionary process by which independent species evolve similar phenotypic traits as a consequence of the adaptation to similar environmental conditions and/or ecological niches. A well-known example of convergent evolution are the wings of birds, insects and bats that evolved separately in these different lineages. Convergent evolution is opposite to divergent evolution in which closely related organisms evolve different phenotypic traits (for example, Darwin's finches, which are closely related species that have both similar and different traits).

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

the actual answer was 160934