Which is a cause of psychological fatigue?

NON SPECIFIC DEFENSES: Skin and Mucous membranes, antimicrobial chemicals, natural killer cells, phagocytosis, inflammation and fever.

Explanation:

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light rays enter the eye through the cornea, the clear front first understand how the eye enables us to see, and what role the cornea plays in eye at different angles, and do not focus on one point the retina, but on many we can tolerate very large scars on our bodies with no concern except for our vanity.

i think itś the 2nd one because its not anything major like having sex. its putting limits to your self if that makes sense.

hope that and feel free to ask me more questions : )

brainliest? ?