Which of the substances listed should be applied to battery terminals to help prevent corrosion?

Correct Answer: Option B — Petroleum jelly

Petroleum jelly, or similar non-conductive grease, creates an airtight barrier over battery terminals. This prevents atmospheric moisture and acid fumes from reacting with the metal, effectively inhibiting the formation of corrosive salts that increase electrical resistance and interfere with the battery's ability to deliver high starting currents.