The specialisation of labour enhances production because people

The specialisation of labour enhances production because people can save time and produce more.

When workers specialise - that is, when each person concentrates on a single task or a narrow range of tasks - they become more skilled and efficient at those specific tasks. This efficiency gain works through several mechanisms:

• Reduced time switching: A worker who performs one task continuously does not lose time moving between different activities, tools, or workstations.
• Increased skill: Repetition builds expertise. A worker who focuses on one operation becomes faster and more accurate at it.
• Greater total output: Because each specialised worker produces more per unit of time, the combined output of all workers rises.

The other options contain important errors. Workers do not become "experts in all areas of production" - specialisation means becoming expert in one specific area. Workers cannot "efficiently produce their own needs" - specialisation actually increases dependence on trade, since each person produces only one thing and must exchange for everything else. And workers do not "concentrate on all goods they can produce better" - they concentrate on the specific good or task where they have the greatest advantage.