Part A
Answer: A. when the audience knows something a character does not
Dramatic irony occurs when the audience is privy to information that the characters within the narrative are unaware of, leading to a heightened emotional experience as the audience anticipates the characters' reactions upon learning the truth.
Part B
Answer: D. We think the—cat got it. (paragraph 27)
This line exemplifies dramatic irony because the audience understands the true significance of the bird's death and what it symbolizes for Mrs. Wright, while the characters (specifically Mrs. Hale and Mrs. Peters) are attempting to cover up the evidence of the dead bird, misleading the men who are searching for clues. The line shows a stark contrast between what the women are trying to imply and the actual implications of the bird's death.