How did Mattie know that she and LaBoeuf were searching for the same man?

• A. They recognized the same scar.
• B. LaBoeuf showed her a picture of Chelmsford. Even without the black mark, she could tell it was Tom Chaney.
• C. They discussed his alias.
• D. They overheard rumors.

Answer: (B)

The idea being tested is recognizing someone by identifying features and known identity. In the scene, LaBoeuf shows Mattie a picture of Chelmsford, who is the alias for Tom Chaney. Mattie can tell that the man in the photo is Tom Chaney, even without the distinguishing black mark, because his face matches what she knows about him. This moment confirms they’re both after the same man.

The other details don’t fit as well: a scar alone isn’t what seals the recognition; simply discussing an alias wouldn’t prove they’re chasing the same person, and rumors aren’t a reliable basis for identifying a suspect.