With a few exceptions, what does the "Unobstructed and Unblocked" element of egress mean?

Answer

The correct option is "Exit doors should not be locked". In fire safety and building codes, an element of egress being "unobstructed and unblocked" primarily means that paths of travel and exit doors must remain completely free from physical barriers, including being unlocked, so that people can evacuate quickly and safely in an emergency without needing special keys, knowledge, or effort.