There is a rare illness called mad cow disease. It is also called as bovine spongiform encephalopathy (BSE). This disease affects cow's nervous system causing a cow to act strangely. According to scientists, a person is at higher risk of getting a human form of the disease, CJD (Creutzfeldt-Jakob disease), when he/she eats BSE-infected meat. You have studied various disease-causing agents. Which agent do you think is responsible for this rare disease for which there is no treatment yet?

Explanation

**Step-by-Step Solution:**

1. **Understanding Mad Cow Disease**: Mad cow disease, scientifically known as bovine spongiform encephalopathy (BSE), is a neurological disorder that affects cows. It leads to abnormal behavior due to its impact on the cow's nervous system.

2. **Human Risk**: When humans consume meat from cows infected with BSE, they are at risk of developing a human form of the disease known as Creutzfeldt-Jakob disease (CJD). This highlights the zoonotic nature of the disease, where it can be transmitted from animals to humans.

3. **Identifying the Causative Agent**: The causative agent responsible for both BSE and CJD is a prion. Prions are misfolded proteins that can induce other normal proteins in the brain to also misfold, leading to severe neurological damage.

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