(b) To create a separation of powers to prevent from authoritarianism.
Checks and balances ensure that the legislature, executive, and judiciary each limit the others' powers, so no single organ exercises unlimited authority.
Source: Forms of power-sharing, Chapter 1
The passage explicitly states: "Each organ checks the others. This results in a balance of power among various institutions… This arrangement is called a system of checks and balances." Option (b) is the only choice that correctly reflects this idea. Options (a), (c), and (d) contradict the democratic principle of distributed power described in the chapter.