Which of the following military uniform items is NOT authorized to wear with civilian attire?

The blue working jacket is not authorized to be worn with civilian attire because it is considered a uniform item specifically designated for official military use. Military uniforms are intended to identify service members in a formal or designated capacity, and regulations typically restrict certain items to ensure that they are worn appropriately within military contexts.

In contrast, the white dress shirt, utility trousers, and service dress coat may have applications outside of categorized uniform wear. For example, a white dress shirt can be worn as a general shirt in civilian dress, utility trousers are often designed to be functional and can sometimes be worn casually, and the service dress coat, while mainly formal, might be seen in particular civilian settings, such as formal occasions where military representation is appropriate.

Thus, the blue working jacket stands out as the item not permitted with civilian clothing, aligning with the policies that govern military attire and its specific purposes.