b. To give the reader a sensation of hearing how someone really thinks
Explanation:
Readers can follow characters' thoughts in real time, allowing them to comprehend not just what they do, but also why they do it. This allows viewers to empathize with the characters rather than criticize them if they make a poor decision because they understand their position and thought process.
This also helps the reader decide who they're rooting for and who they just...dislike.
