## **Core Concept**
The question tests knowledge of ovarian tumors, specifically focusing on tumor markers and ultrasound characteristics. Ovarian tumors can be broadly classified into epithelial, germ cell, and sex cord-stromal tumors. Tumor markers play a crucial role in diagnosing and differentiating these types.

## **Why the Correct Answer is Right**
The correct answer, **D. Dysgerminoma**, is a type of germ cell tumor. Dysgerminomas are known for being predominantly solid on imaging and for elevating lactate dehydrogenase (LDH) levels, not CA-125 or alpha-fetoprotein (AFP). CA-125 is often elevated in epithelial ovarian cancers, while AFP is typically elevated in yolk sac tumors (another type of germ cell tumor). The patient's presentation and lab findings align well with dysgerminoma.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is blank and cannot be evaluated.
- **Option B:** This option is blank and cannot be evaluated.
- **Option C:** This option is blank and cannot be evaluated.
- **Option A, B, C are incorrect** because they do not match the description provided for a tumor that would have elevated LDH, negative CA-125, and negative AFP.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **LDH is often elevated in dysgerminomas**, which helps differentiate them from other ovarian tumors. Dysgerminomas are also **highly sensitive to radiotherapy**, making them a unique tumor in terms of both diagnosis and treatment.

## **Correct Answer:** **D. Dysgerminoma**