Answer : Option B) Plant stomata opening and closing to maintain homeostasis.
Explanation : Claude Bernand was a French Physiologist who first discovered about "homeostasis" which is defined as the controlled stability of the internal milieu, or internal environment, of cells and tissues in plants.
In plants stomatal opening and closing was done for maintaining homeostasis with the external and internal plant environment.
Excess intake of antibiotics is harmful because too much can change bacteria so much that antibiotics don't work against them. So technically your teaching good bacteria to be bad.