What must every lamp comply with according to FMVSS/CMVSS requirements?

Answer: C — Must be permanently attached and meet specified requirements

Every lamp on a vehicle must be permanently attached and adhere to specific requirements as outlined in the FMVSS (Federal Motor Vehicle Safety Standards) or CMVSS (Canadian Motor Vehicle Safety Standards). This is critical for ensuring that lamps operate reliably during vehicle use, which contributes to overall safety on the road. Permanently attaching lamps prevents them from becoming dislodged or detached, which could lead to reduced visibility or failure to signal properly to other road users. In addition to the requirement for permanence, these standards also stipulate performance criteria that the lamps must meet, such as brightness, color, and functional reliability. Compliance ensures that the lamps serve their purpose effectively, helping to maintain safety standards and protect drivers, passengers, and pedestrians alike. Other options do not directly address the essential safety considerations mandated by law. While flexibility or brightness may have some importance in specific contexts, they do not carry the same legal weight or emphasis in the standards as the requirement for permanent attachment and compliance with performance specifications.