During which period must winter uniforms be worn?

The correct answer is that winter uniforms must be worn from October 15 to April 30. This timeframe is specifically designated for winter attire as it corresponds to the colder months when appropriate warm clothing is needed for outdoor work conditions.

During this period, employees are expected to maintain a standard of professionalism while also being dressed suitably for the climate. The inclusion of different uniforms year-round indicates attention to both comfort and the practical needs of workers in varying weather conditions.

The remaining options do not align with the standard practice of seasonal uniform requirements; for instance, the months listed in other choices either extend into warmer months or do not cover the entire winter period, leading to inconsistencies with overall uniform policies.