Final answer:
Jem reacts with anger to Scout's question about Mrs. Gates's prejudice, reflecting his disillusionment with the racial injustice in their society after Tom Robinson's trial.
Step-by-step explanation:
In Harper Lee's novel To Kill a Mockingbird, Jem reacts with anger and frustration to Scout's question about Mrs. Gates's prejudice against Tom Robinson. This reaction comes after the trial of Tom Robinson, where Jem's hopes for justice are crushed by the racially biased verdict. His strong emotional response likely stems from his disillusionment with the racial injustice prevalent in their society and the contrasting values of fairness and equality that Atticus has taught him. Jem's maturation and moral awakening during the trial lead him to have a more complex understanding of the world, which is why he finds the hypocrisy of Mrs. Gates, who condemns Hitler's prejudice in the classroom but then displays prejudice herself, so unbearable.