very high melting point gas state at room temperature good conductor of electric current extremely brittle solid at room temperature
I gave my students this multiple choice question: What physical property is characteristic of all of the elements in the group located in the rightmost column of the periodic table?

Only one answer is correct among these 4 choices:
- very high melting point
- gas state at room temperature
- good conductor of electric current
- extremely brittle solid at room temperature

Could you tell me which one is correct?

gas state at room temperature