Which of the following fire extinguishing agents which may be found aboard ship is designated as an ozone-depleting substance as defined in the Montreal Protocol on Substances that Deplete the Ozone Layer and is controlled as a result?

Correct Answer: Option B — Halon 1301

Halon 1301 is a potent ozone-depleting substance categorized under the Montreal Protocol. Due to its high ozone depletion potential, its use in new fire extinguishing systems is prohibited, and existing installations are strictly regulated to prevent accidental release into the atmosphere during maintenance or system testing.