C
Below is a question with multiple-choice answers. Choose the correct option based on your reasoning.

### Question:
During a lecture, a professor was talking about the potential that hydrogen has for exploding under certain conditions. Which was most likely the topic of the professor's lecture?

### Choices:
A. Conductivity of Gases
B. Phase Changes in Matter
C. Chemical Properties of Gases
D. Physical Properties of Elements

### Answer:
