According to Maxwell’s hypothesis, a changing electric field gives rise to

Options

A. an e.m.f
B. electric current
C. magnetic field
D. pressure gradient

Answer

To solve the question "According to Maxwell’s hypothesis, a changing electric field gives rise to," we will analyze the options provided and apply Maxwell's equations to reach the correct conclusion.

### Step-by-Step Solution:

1. **Understanding Maxwell's Hypothesis**:
- According to Maxwell's equations, particularly Faraday's law of induction, a changing electric field can induce a magnetic field. This is a fundamental concept in electromagnetism.

2. **Analyzing the Options**:
- **Option A: emf (Electromotive Force)**: While a changing electric field can be related to emf, it is not the direct result of a changing electric field according to Maxwell's hypothesis.
- **Option B: Electric Current**: A changing electric field does not directly create an electric current; rather, it can induce a magnetic field that may influence current flow.
- **Option C: Magnetic Field**: This is the correct option. A changing electric field indeed gives rise to a magnetic field, as per Maxwell's equations.
- **Option D: Pressure Gradient**: This option is unrelated to the context of electromagnetic fields and is incorrect.

3. **Conclusion**:
- Based on Maxwell's hypothesis, the correct answer is that a changing electric field gives rise to a **magnetic field**.

### Final Answer:
A changing electric field gives rise to a **magnetic field**.

---