The correct statement is:
He becomes convinced of Hyde’s evil capacity.
Throughout the story, Mr. Utterson's relationship with Hyde evolves, and he becomes increasingly convinced of Hyde's evil capacity. Initially, Mr. Utterson is cautious and suspicious of Hyde, as he senses something unsettling about him. As he investigates further, he discovers Hyde's involvement in disturbing incidents, including a murder. These discoveries solidify his belief in Hyde's malevolence and understanding that Hyde poses a threat to society.
Mr. Utterson's growing conviction about Hyde's evil nature is evident in his persistent pursuit of the truth. He is determined to protect his close friend Dr. Jekyll from any harm from his association with Hyde. Mr. Utterson's sense of duty and responsibility to his friend drives him to uncover the truth behind Hyde's actions. This leads him to believe Hyde's capacity for evil.
As the story progresses, Mr. Utterson's relationship with Hyde shifts from cautious suspicion to a deep-seated belief in Hyde's wickedness. This development underscores the theme of duality and the battle between goodness and evil in human nature. Mr. Utterson's conviction about Hyde's sinister nature ultimately drives him to take action and attempt to bring justice to Hyde. This reveals the depth of his belief in Hyde's capacity for evil.