Which structures produce a fluid to protect the body in the first line of defense? Select four options.hairstomachmoutheyesskin

The stomach produces acidic gastric fluid, the mouth produces saliva, the eyes produce tears, and the skin produces sweat and oils. These fluids help trap, wash away, or destroy pathogens as part of the body's first line of defense. Hair can provide a physical barrier, but it does not produce a protective fluid.

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