Answer: He shows them a picture of Lise
Explanation: In this chapter from "Number the Stars" by Lois Lowry, Mr. Johansen convinced the German soldiers that Ellen was not a Jewish girl hiding by showing them a picture of Lise. The story takes place in the third year of the German occupation of Denmark. Annemarie is a ten-year-old Danish girl and her best friend is Ellen, a Jewish girl. When the German soldiers ask who is the dark-haired girl, meaning Ellen, Mr. Johansen shows them a picture of his dead daughter Lise as a baby, to convince them she is not a Jewish girl hiding.