At what temperature do all materials or substances still contain heat?

The correct answer reflects the concept of absolute zero, which is the theoretical temperature at which a substance contains minimal thermal energy. This temperature is defined as -273.15 degrees Celsius or -459.67 degrees Fahrenheit. At absolute zero, the motion of atoms is at its lowest possible energy state, meaning that while it is impossible to reach this temperature, it is considered the point at which all molecular motion ceases.

In real-world applications, no material can reach absolute zero due to the third law of thermodynamics; however, this temperature serves as an important reference point in thermodynamics and for understanding how heat is measured and described in terms of absolute temperature scale.

The other temperatures listed, such as 0 degrees Fahrenheit, -273 degrees Celsius, and 32 degrees Fahrenheit, do not represent absolute zero and therefore do not signify a state where all materials lack heat energy. Instead, they represent various states of temperature that fall well above absolute zero, at which point materials will continue to possess heat energy and exhibit atomic movement.