What is absolute zero in degrees Celsius?

Absolute zero is the theoretical temperature at which a system's entropy reaches its minimum value, leading to a complete absence of thermal energy. In the Celsius scale, this temperature is defined as -273 degrees Celsius. At this point, the motion of atoms theoretically comes to a halt, and no further energy can be extracted from the system.

When discussing the temperatures in other answer choices, it's important to note that -100 degrees Celsius, 0 degrees Celsius, and -459 degrees Celsius do not represent absolute zero. Zero degrees Celsius is the freezing point of water, while -100 degrees Celsius is much warmer than absolute zero. -459 degrees Celsius is a temperature in Fahrenheit, not Celsius, and is also inaccurate in describing absolute zero in either scale. Therefore, -273 degrees Celsius is the correct representation of absolute zero in the Celsius scale.