Final answer:
Relative units of measurements provide the advantage of being adaptable to various screen sizes and devices, offering flexibility needed for responsive web design.
Step-by-step explanation:
An advantage of using relative units of measurements over hard-coded measurements is that relative units adapt to different screen sizes and devices. Unlike hard-coded measurements that are fixed, relative units allow for flexibility in design, which is particularly beneficial in responsive web design. This flexibility ensures that web content is easily viewable on various devices, from desktop computers to mobile phones, without needing to define multiple sets of sizes for each device.