Why do people often choose to live in cities? How can that impact culture?

People choose to live in cities because of more opportunities in life. This can result in dying out of rural cultures, though often some elements are incorporated with the city culture.

Explanation:

Cities have always been attractive for people, and they have gained even more popularity after the Industrial Revolution. The cities are offering much more opportunities in life than any other place, so naturally, people want to have a better life as possible so they abandon the rural areas.

This switch of population impacts culture as well. In most cases, the rural cultures tend to suffer from it, as gradually they lose people that practice them and eventually die out as such. In some cases, if there is a massive migration from a particular region, because of the high number of a new population with the same cultural characteristics they manage to have an impact on the city culture, so a mix of the two occurs.

a. i. only is correct.