Who appoints the prime minister

I assume you mean in the United Kingdom?

In the United Kingdom the prime minister is appointed by the Queen (or King) who chooses the person who is most likely to have a majority in the House of Commons (most likely the leader of the winning party)

The correct answer is a. when they started making tools that will them in cultivating lands, they could raise crops and that made them attached to one place for a longer period of time. after that, they started domesticating animals and building their own permanent settlements that resemble the ones we have today.