Final answer:
Oxygen binding to myoglobin and hemoglobin is crucial to sustain aerobic respiration during muscle activity, as it facilitates oxygen transport to tissues, ensuring sufficient ATP production for muscular function.
Step-by-step explanation:
It is essential for oxygen to continuously bind to myoglobin and hemoglobin during muscle activity in order to sustain aerobic respiration (Option C). Myoglobin and hemoglobin serve as oxygen carriers, ensuring an ample supply for the aerobic production of ATP. During heightened muscle activity, this is particularly crucial as the demand for ATP increases. Through aerobic respiration, muscles are able to maintain prolonged activity, instead of quickly reverting to anaerobic respiration, which leads to the production of lactic acid.
In terms of the other options, myoglobin and hemoglobin aren't directly related to preventing the buildup of lactic acid (Option A), maintaining muscle elasticity (Option B), or regulating calcium ion concentration (Option D). Instead, their primary role is to facilitate oxygen transport from the lungs to tissues, which is vital for muscular function.