Which of the following is a compound?

Options

A. Ozone
B. Marble
C. Diamond
D. Quick silver

Answer

To determine which of the given options is a compound, we need to analyze each option based on the definition of a compound. A compound is a substance formed when two or more different types of atoms bond together in a fixed ratio.

### Step-by-Step Solution:

1. **Analyze Option A: Ozone (O₃)**
- Ozone is a molecule consisting of three oxygen atoms.
- Since it is made up of only one type of atom (oxygen), it is not a compound.
- **Conclusion**: Ozone is not a compound.

2. **Analyze Option B: Marble (CaCO₃)**
- Marble is chemically known as Calcium Carbonate (CaCO₃).
- The formula indicates that it is composed of three different types of atoms: Calcium (Ca), Carbon (C), and Oxygen (O).
- Since it contains more than one type of atom, it qualifies as a compound.
- **Conclusion**: Marble is a compound.

3. **Analyze Option C: Diamond (C)**
- Diamond is a form of carbon and consists solely of carbon atoms.
- As it is made up of only one type of atom, it is not a compound.
- **Conclusion**: Diamond is not a compound.

4. **Analyze Option D: Quicksilver (Hg)**
- Quicksilver is the common name for mercury, which is a single element.
- Since it consists of only one type of atom (mercury), it is not a compound.
- **Conclusion**: Quicksilver is not a compound.

### Final Answer:
Based on the analysis, the only option that is a compound is **Option B: Marble (CaCO₃)**.