Explanation:

Here's an explanation of each option:

- Option 1: Alternatives to hydrofluorocarbon refrigerants

- These are substances used to replace HFCs in refrigeration, unrelated to CL-20, HMX, and LLM-105.

- Option 2: Explosives in military weapons

- Correct Answer: All three substances, CL-20, HMX, and LLM-105, are advanced explosives used in military applications for their powerful explosive capabilities.

- Option 3: High-energy fuels for cruise missiles

- While high-energy fuels are important for missiles, these substances are primarily characterized as explosives, not fuels.

- Option 4: Fuels for rocket propulsion

- CL-20, HMX, and LLM-105 are not used as rocket fuels. They are explosives.