Man is the definitive host for -a) E. granulosusb) T. Soliumc) T. Saginatad) T. Cannise) E. Multilocularis

**Question:** Man is the definitive host for - a) E. granulosus, b) T. solium, c) T. saginata, d) T. cannis, e) E. multilocularis.

**Core Concept:** Definitive hosts are species that harbor parasites inside their bodies, allowing the parasites to complete their life cycle. In the context of the question, we are discussing parasites found in humans and their life cycles.

**Why the Correct Answer is Right:** Among the given options, man (Homo sapiens) serves as the definitive host for two parasites:

1. **Echinococcus granulosus (Option A):** E. granulosus is a tapeworm belonging to the genus Echinococcus. Humans act as the final host in the life cycle of E. granulosus, which involves intermediate hosts such as sheep, goats, and cows. The parasite enters the human body when a cyst-carrying intermediate host is consumed, leading to the development of the disease called hydatidosis or cystic echinococcosis.
2. **Taenia solium (Option B):** T. solium, commonly known as the pork tapeworm, is another tapeworm responsible for causing neurocysticercosis in humans. Humans are the definitive host, with the parasite originating from the consumption of infected pork products by humans.

**Why Each Wrong Option is Incorrect:**

3. **Taenia saginata (Option C):** This option refers to the beef tapeworm, which is not relevant to humans as humans are not the definitive host for T. saginata. The parasite originates from the consumption of undercooked beef contaminated with Taenia solium cysts.
4. **Taenia canis (Option D):** T. canis is the tapeworm responsible for causing taeniasis in dogs, not humans. Humans are not the definitive host for T. canis.
5. **Echinococcus multilocularis (Option E):** E. multilocularis is responsible for alveolar echinococcosis, also known as alveolar hydatid disease. Humans are not the definitive host for E. multilocularis, which primarily affects animals like foxes, raccoons, and badgers.

**Clinical Pearl:** Taenia solium is the only parasite among the given options that is directly linked to human health, as it causes neurocysticercosis, a parasitic infection of the central nervous system. Ingestion of Taenia solium eggs leads to the development of cysticerci cysts within the human brain or other tissues, causing disease.

In conclusion, the correct answer is Taenia solium (Option B), and the incorrect options refer to parasites that primarily infect dogs (Taenia canis), foxes (Echinococcus multilocularis), and cattle (Taenia saginata).