Final answer:
Dehydrogenases primarily transfer hydrogens between substrates and are known to transfer hydride ions to the electron carriers NAD+ or NADP+ while releasing a proton. The other options provided in the question describe different enzymatic activities or reactions, so the correct answer is focused on hydrogen and hydride transfer.
Step-by-step explanation:
Dehydrogenases are a class of enzymes that fall under the category of oxidoreductases. They are crucial for various oxidation-reduction reactions in the cellular metabolic processes. Primarily, these enzymes are involved in the transfer of hydrogens between substrates, especially during cellular respiration.
Anaerobic dehydrogenases use other substrates to donate hydrogen instead of directly to oxygen and transfer hydrogens to such acceptors like NAD+, FAD, and FMN. Notably, aerobic dehydrogenases remove hydrogen from the substrate to add either directly to oxygen to form water or to other acceptors, producing hydrogen peroxide. Importantly, enzymes like lactate dehydrogenase and glutamate dehydrogenase facilitate the removal of hydrogens with the concomitant reduction of NAD+ to NADH
Given the enzyme functions presented, the correct option that fits the activities of dehydrogenases is that they transfer hydride ions to NAD+ (or NADP+) and release a proton. Options a, b, and c are activities associated with different types of enzymes or reactions, not specifically dehydrogenase activity.
Dehydrogenases are involved in the transfer of hydrogens between substrates, especially transferring hydride ions to NAD+ (or NADP+) and releasing a proton. Other options describe activities related to different enzymes or enzymatic reactions.