**Core Concept**
Plasmodium falciparum is a protozoan parasite that causes the deadliest form of malaria, characterized by its ability to infect and damage various organs of the human body. The parasite invades and multiplies within erythrocytes, leading to systemic complications.

**Why the Correct Answer is Right**
The parasite can affect the lungs by causing pulmonary edema and respiratory distress due to the severe anemia and hypoxia it induces. **Plasmodium falciparum** can also infect the liver, causing liver dysfunction and damage. In the kidneys, the parasite can lead to acute kidney injury and renal failure. Additionally, the parasite can affect the heart by causing myocarditis and cardiac dysfunction.

**Why Each Wrong Option is Incorrect**
**Option A:** Lung - Incorrect because, although the lungs are not the primary site of infection, severe malaria can cause pulmonary complications, making this option incorrect.
**Option B:** Liver - Incorrect because, as mentioned earlier, **Plasmodium falciparum** can infect the liver and cause liver dysfunction.
**Option C:** Kidney - Incorrect because the parasite can lead to acute kidney injury and renal failure in severe cases.
**Option D:** Heart - Incorrect because the parasite can cause myocarditis and cardiac dysfunction, affecting the heart.

**Clinical Pearl / High-Yield Fact**
It's essential to note that **Plasmodium falciparum** can cause cerebral malaria, a life-threatening complication that requires prompt recognition and treatment.

**Correct Answer:** D. Heart