In the context of Gibbs free energy, when ATP is hydrolyzed (loses a terminal phosphate group to form ADP and inorganic phosphate), what is released that can be used to drive cellular work?

• A. A net gain of Gibbs free energy ($\Delta G>0$) stored in ATP products
• B. Free energy (a decrease in Gibbs free energy, $\Delta G<0$)
• C. Molecular oxygen ($O_2$) as a direct product of ATP phosphate loss
• D. Only heat energy, with no change in Gibbs free energy ($\Delta G=0$)

Answer: (B)