<span>The state in which the body's systems are functioning smoothly and in equilibrium </span>is called homeostasis.
<span>Homeostasis is the tendency to maintain a balanced (relatively constant) internal environment and it can also be defined as the stable state of an organism. Homeostasis is maintained at many levels, not just the level of the whole body (blood sugar levels, pH, fluid balance…). Each of these is controlled by one or more homeostatic mechanisms (feedbacks for example).</span>
When you blink a film of tear fluid coats the surface of you eye at a certain thickness and is maintained for a while. Tears contain a substance called lysozyme, which has an antibacterial action, and works to prevent invasion and infection by microbes.
(sorry I put the answer in the comments I'm new to this haha)
ITS LETTER B THE AWSERS IS B