I think it would be compound because they're both a compound. Not both of them are an Element, and not both of them would be a Solution. A heterogeneous mixture isn't right either so.. The correct answer is D) Compound.
Gas laws re the laws that relates properties of gases such as pressure, temperature and volume at different conditions.
Gas laws includes, Boyle's law, Charles law, grahams law and pressure law among others.
Temperature is one of the quantity of gases explained by gas laws. For gas laws to work, temperature should always be in Kelvin. Therefore, when given temperature in degrees, it is converted to Kelvin by adding 273, that is °C + 273 = K.
