**Core Concept**
The question tests the understanding of antihelminthic medications with immunomodulatory properties, which are crucial in the treatment of parasitic infections. These medications not only target the parasites but also modulate the host's immune response to enhance the body's natural defenses.

**Why the Correct Answer is Right**
Praziquantel is a widely used antihelminthic medication that also exhibits immunomodulatory effects. It works by increasing the production of cytokines, such as IL-12 and IFN-γ, which are essential for activating the immune response against parasitic infections. Additionally, praziquantel has been shown to enhance the activity of natural killer cells and macrophages, further augmenting the host's immune response.

**Why Each Wrong Option is Incorrect**
* **Option A:** Albendazole is an antihelminthic medication, but it primarily works by inhibiting the polymerization of microtubules in the parasite's cytoskeleton, leading to its death. It does not have significant immunomodulatory effects.
* **Option B:** Ivermectin is another antihelminthic medication that works by activating glutamate-gated chloride channels in the parasite's nervous system, leading to muscle paralysis and death. While it has some immunomodulatory effects, they are not as pronounced as those of praziquantel.
* **Option C:** Metronidazole is an antibiotic and antiprotozoal medication that works by inhibiting the synthesis of DNA and RNA in microorganisms. It does not have any significant immunomodulatory effects.

**Clinical Pearl / High-Yield Fact**
Praziquantel is often used in combination with other antihelminthic medications to enhance its efficacy and reduce the risk of resistance. It is also being explored as a potential treatment for certain autoimmune diseases due to its immunomodulatory effects.

**Correct Answer:** A. Praziquantel