In pure shark liver oil “Alkoxyglycerol” are unique in supporting:

Correct option is A

Alkoxyglycerols (alkylglycerols) in shark liver oil have immunomodulatory properties—stimulating leukocyte activity and enhancing immune responses.
Biological Action
Effects: promote macrophage function, may increase white blood cell proliferation, support recovery.
Sources: shark liver oil, cod liver oil (to a lesser extent), bone marrow.
Research: used in complementary medicine; some clinical interest in cancer-supportive therapies (adjunctive), though evidence levels vary.
Applications / Cautions
Marketed as dietary supplements for immune support.
Consumers should consider source sustainability and contamination (mercury, PCBs) in some marine oils.
Notes on other options
Not primarily for muscle protein synthesis, arthritis treatment, or rickets (vitamin D related).