Is the optimal growth range the temperature range at which an organism's metabolic systems function least efficiently?

The statement that the optimal growth range is the temperature range at which an organism's metabolic systems function least efficiently is incorrect. The optimal growth range actually refers to the specific temperature range in which an organism's metabolic processes operate most effectively, leading to the highest rates of growth and reproduction.

At temperatures outside of this optimal range, metabolic activities can become less efficient, leading to slower growth rates, metabolic distress, or even cell death if the temperatures are extreme. Therefore, the correct understanding aligns with option B: the optimal growth range is where metabolic efficiency is maximized, not minimized.

This concept is crucial in microbiology, as it helps microbiologists understand the environmental conditions necessary for the growth and survival of various microorganisms.