**Core Concept:** Autosomal dominant inheritance refers to a genetic condition that is passed down from parents to children based on their X and Y chromosomes. The offspring has a 50% chance of inheriting the condition, regardless of gender. Dominant traits are expressed when one copy of the gene is sufficient for the trait to appear. Adolescence typically refers to the period between childhood and adulthood, typically encompassing ages 12-21.

**Why the Correct Answer is Right:** The correct answer, **D. Ehlers-Danlos Syndrome (EDS)**, is an autosomal dominant genetic disorder affecting connective tissue, specifically collagen synthesis and deposition. Collagen is the primary component of skin, blood vessels, and other tissues that support the body, and its proper synthesis is crucial for maintaining tissue integrity. In EDS, affected individuals experience joint hypermobility, skin laxity, and a predisposition to dislocations, ruptures, and arterial rupture. The onset of symptoms typically occurs during adolescence, making it an appropriate answer.

**Why Each Wrong Option is Incorrect:**

A. **Cushing's syndrome (CS)** is a hormonal disorder caused by prolonged exposure to high levels of cortisol. It is not an autosomal dominant trait and usually presents in adulthood, not adolescence.

B. **Klinefelter's syndrome** is an X-linked genetic disorder involving the absence or extra presence of the X chromosome in males. It affects spermatogenesis and hormonal balance, leading to infertility, gynecomastia, and short stature. Unlike EDS, it is X-linked and does not affect females, making it irrelevant for this question.

C. **Marfan syndrome** is an autosomal dominant genetic disorder affecting connective tissue, causing cardiovascular, ocular, and skeletal manifestations. However, it typically presents during childhood or early adulthood, not adolescence.

**Clinical Pearl:** Recall the importance of considering genetics and inheritance patterns when evaluating patients during adolescence for potential genetic disorders. Familiarize yourself with the classic clinical presentations of disorders like EDS, Marfan syndrome, and Klinefelter's syndrome to promptly identify and refer patients for appropriate genetic counseling and management.