The right option is; The small crowd of protesters had turned into an angry mob.
The third-person point of view is a form of writing in which a narrator expresses all the action of his work using a third-person pronoun such as he, she, they, them, their, his, and hers. A third-person point of view may be limited in which the narrator only expresses his own thoughts and knowledge about a situation, and it may be omniscient, in which the narrator expresses all of the character’s thoughts and feelings in the story
