Contractors must always comply with which legal requirement?

The correct answer is that contractors must always comply with state wage and hour laws. This is essential because state laws dictate various aspects of employment, including minimum wage, overtime pay, and working conditions, which can vary significantly from one state to another. By adhering to these laws, contractors ensure fair treatment of workers and avoid legal consequences that can arise from non-compliance.

In the context of the construction and asbestos removal industries, where contractors frequently work on projects that span multiple states or regions, being well-versed in the specific wage and hour laws of the state in which they operate is critical. These regulations are designed to protect workers' rights and ensure they are compensated fairly for their labor.

The other options reference specific state wage codes and federal standards but do not encapsulate the broader legal requirement that pertains universally to contractors across various states—state wage and hour laws.