`X’ melts at low temperature and is a bad conductor of electricity in both liquid and solid state. X is:

Options

A. Zinc sulphide
B. Mercury
C. Silicon carbide
D. Carbon tetrachloride

Answer

To solve the question, we need to analyze the properties of the substance 'X' based on the information given:

1. **Identify the properties of 'X':**
- Melts at low temperature.
- Is a bad conductor of electricity in both liquid and solid states.

2. **Understanding conductivity:**
- A bad conductor of electricity typically indicates that the substance does not have free ions or electrons to carry electric current.
- Non-polar molecules or covalent compounds often exhibit this behavior.

3. **Analyzing the options:**
- We need to consider substances that are known to melt at low temperatures and do not conduct electricity well.
- For example, carbon tetrachloride (CCl4) is a non-polar molecule that melts at a low temperature and is a poor conductor of electricity.

4. **Eliminate other options:**
- Zinc sulfide (ZnS) can ionize and conduct electricity.
- Mercury (Hg) is a metal and a good conductor.
- Silicon carbide (SiC) is also a semiconductor and can conduct electricity.

5. **Conclusion:**
- Based on the properties and the analysis, the substance 'X' is most likely carbon tetrachloride (CCl4).

### Final Answer:
X is carbon tetrachloride (CCl4).