**Core Concept**
Human Papillomavirus (HPV) is a common sexually transmitted infection that can lead to cervical cancer, particularly in young women. Regular screening for HPV can help prevent cervical cancer by detecting abnormal cell changes early.

**Why the Correct Answer is Right**
HPV vaccination is recommended for all sexually active women under the age of 26, especially those with a history of multiple sexual partners. However, for those who are already sexually active and not vaccinated, HPV DNA testing is the most appropriate screening test. This is because HPV DNA testing can detect the presence of high-risk HPV types that are associated with cervical cancer, allowing for early intervention. The American College of Obstetricians and Gynecologists (ACOG) recommends HPV DNA testing for women aged 25-65 years who have a normal Pap smear result.

**Why Each Wrong Option is Incorrect**
**Option A:** Pap smear testing is not the best initial screening test for sexually active young women. While Pap smears are effective for detecting abnormal cell changes, they do not directly test for HPV infection.
**Option B:** Colposcopy is a diagnostic procedure used after an abnormal Pap smear result, not a screening test for asymptomatic women.
**Option C:** Cervical cancer screening is not indicated in this patient, as her examination is unremarkable and she has no symptoms.

**Clinical Pearl / High-Yield Fact**
HPV vaccination is most effective when administered before sexual debut, ideally to girls aged 11-12 years. However, for those who are already sexually active, HPV DNA testing is the best initial screening strategy.

**Correct Answer: D**