Among the Natural Defenses Present in Tears Is the Protein

Among the natural defenses present in tears is the protein lactoferrin. As you can infer from its name, it is also present in milk and other body secretions, and its function involves binding iron ions.
The presence of lactoferrin in tears is protective against bacterial infection because _______.

A) all pathogens must acquire iron from their environment and lactoferrin ensures that the iron concentration is low
B) in the presence of lysozyme, as found in tears, the proteins form a protective barrier on the lens
C) pathogens with magnetosomes will be segregated from the eye tissue and swept away by the tears
D) free iron serves as an immune signal to recruit T cells to the eye