## **Core Concept**
The treatment of *Plasmodium vivax* malaria involves targeting both the erythrocytic and liver stages of the parasite to prevent relapse and ensure complete cure. *P. vivax* has a dormant liver stage known as hypnozoites, which can cause relapses if not treated.

## **Why the Correct Answer is Right**
The correct answer involves the use of **chloroquine** or **artemisinin-based combination therapies (ACTs)** for the blood stage, along with **primaquine** to target the liver hypnozoites. Chloroquine is effective against the erythrocytic stages, while primaquine is specifically used to eliminate the hypnozoites in the liver, preventing future relapses.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option might suggest treatment with only chloroquine, which would not target the liver hypnozoites and thus would not prevent relapses.
- **Option B:** This could imply the use of certain drugs that are not recommended for *P. vivax*, such as **sulfonamides** or **trimethoprim-sulfamethoxazole**, which are not standard treatments.
- **Option C:** This might propose a treatment effective for other types of malaria but not specifically tailored for *P. vivax*, such as **mefloquine** or **atovaquone-proguanil**, which do not include primaquine.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **primaquine** can cause **hemolysis** in individuals with **G6PD deficiency**. Therefore, screening for G6PD deficiency is recommended before administering primaquine, especially in areas where G6PD deficiency is common.

## **Correct Answer:** D. Chloroquine + Primaquine.