How do the concepts of "live load" and "dead load" differ in code calculations?

The correct choice highlights the distinction between dead load and live load in structural engineering. Dead load refers to the static load that is always present on a structure, such as the weight of the building materials, fixtures, and other permanent features. This load does not change over time and is a critical factor in determining the structural integrity and design of a building.

On the other hand, live load encompasses transient and variable forces acting on a structure, such as the weight of occupants, furniture, and other movable objects. Live loads can change based on usage patterns, occupancy, and other factors, which means they must be considered carefully during design to ensure safety and stability.

This understanding is essential for engineers and architects to design structures that can safely support not only their own weight but also accommodate fluctuations in loads over time.