Question

which substance must be present to release energy from glucose?
a hydrogen
b oxygen
c lactic acid
d carbon dioxide

Explanation:

To release energy from glucose, cellular respiration (aerobic) requires oxygen. Glucose reacts with oxygen in this process to produce energy, carbon dioxide, and water. Hydrogen isn't the key substance for energy release from glucose in this context. Lactic acid is a product of anaerobic respiration, not a required substance for energy release from glucose. Carbon dioxide is a product, not a reactant needed for energy release from glucose. So oxygen (option B) is necessary.

Answer:

B. oxygen