Tears and mucus membranes would be a part of which defense system? view available hint(s) tears and mucus membranes would be a part of which defense system? innate internal defenses adaptive defenses innate external defenses

Tears and mucus membranes would be a part of the innate external defenses. 
Body protection from outside from invaders involves the skin and the mucous membrane. All external and the internal surfaces of the human body are key element of the innate immune system.  Chemical substances like tears, acids, enzymes or mucous prevent pathogens and viruses from gaining entry to the body.

They must use the scientific method