**Core Concept**
Toxocariasis is a parasitic infection caused by Toxocara species, which can lead to tissue damage and inflammation in various organs, including the heart. Myocarditis, or inflammation of the heart muscle, can be a rare but serious complication of toxocariasis.

**Why the Correct Answer is Right**
Trichinella spiralis, the parasite responsible for trichinosis, can cause myocarditis through the invasion of muscle tissue, including the heart. This leads to an inflammatory response and damage to the heart muscle. The larvae of Trichinella spiralis can penetrate the intestinal wall and migrate to the muscles, where they encyst and cause inflammation.

**Why Each Wrong Option is Incorrect**
**Option A:** Toxocara species are not typically associated with myocarditis, although they can cause tissue damage and inflammation in other organs.
**Option B:** Angiostrongylus cantonensis, the rat lungworm, primarily causes eosinophilic meningitis and is not typically associated with myocarditis.
**Option C:** Strongyloides stercoralis, the threadworm, can cause a range of symptoms, but myocarditis is not a common or well-documented complication.

**Clinical Pearl / High-Yield Fact**
Trichinosis is often acquired through the consumption of undercooked or raw meat, particularly pork, and can be prevented by proper cooking and food handling practices.

**Correct Answer:** C. Trichinella spiralis.