Consider the following statements regarding photosynthesis and respiration in plants and select the correct option.

I. RuBisCO has a high affinity for oxygen in low $CO_2$ concentration.
II. The Calvin pathway occurs in the chloroplast of bundle sheath cells of $C_4$ plants.
III. Yeast poisons itself when the concentration of alcohol reaches 7%.
IV. Oxygen is a final hydrogen acceptor during aerobic respiration.