Which organization focuses on unlicensed deck personnel on the West Coast?

The correct choice relates to the Sailors' Union of the Pacific (SUP), which is particularly focused on unlicensed deck personnel on the West Coast. This organization represents and advocates for the rights and welfare of sailors in these roles, ensuring they receive proper working conditions, wages, and support.

The SUP operates predominantly in Pacific Coast ports and is known for its active involvement in maritime labor issues. This includes negotiating contracts, providing legal assistance, and facilitating training and employment opportunities for its members, which are chiefly composed of unlicensed deckhands and related maritime roles.

While the other organizations focus on various aspects of maritime labor, they do not specifically target unlicensed deck personnel on the West Coast. Each has its own area of focus–for instance, MFOW (Maritime Federation of Workers) and IBU (International Longshoremen's and Warehousemen's Union) have different membership and represent different sectors of maritime work. SUI, which stands for Seafarers Union International, may also cover broader areas within the maritime industry but does not specialize exclusively in the needs of unlicensed deck personnel in the region specified. Thus, the specificity of the SUP makes it the fitting answer in this context.