What definition fits a common carrier in maritime transport?

A common carrier in maritime transport is defined by its obligation to provide transportation services to the public without discrimination. This means that it must carry any legal cargo presented to it, provided that the cargo is appropriate for the vessel and the shipper is willing to pay the required rates. This principle is foundational in the shipping industry, ensuring that all customers have access to transportation services for their goods, which promotes fairness and competition.

The other options highlight different operational models or restrictions that do not apply to common carriers. Operating solely on chartered routes pertains to chartered vessels rather than common carriers. Focusing exclusively on hazardous materials describes a specialized type of transport service that is not characteristic of all common carriers, which handle a wide array of cargo types. The option allowing refusal of cargo at discretion is more aligned with private carriers or specialized services, which do not have the same obligation as common carriers. Understanding these distinctions is crucial for grasping the foundational principles of maritime transport operations.