A nurse in the emergency department is assessing a preschooler who has a facial laceration. The nurse should identify which of the following findings as a potential indication of child sexual abuse?

A. This is correct because discomfort while walking can indicate genital trauma or infection, which are possible signs of sexual abuse. B. This is incorrect because thin extremities can be caused by many factors, such as malnutrition, genetic disorders, or chronic diseases, that are not necessarily related to sexual abuse. C. This is incorrect because bruises on the upper back can result from accidental injuries, such as falls or bumps, or from physical abuse, such as hitting or kicking, but not specifically from sexual abuse. D. This is incorrect because a stained shirt can be due to poor hygiene, food spills, or environmental factors, but not necessarily from sexual abuse.