Why is it easier for a large circuit breaker to interrupt AC than DC?

1. When a breaker opens on a high voltage, a spark can jump the gap and ionize the air in it. 2. That ionized path lets the current keep flowing, so the circuit is not really interrupted. 3. A 60-Hz AC current passes through zero 120 times every second, twice in each cycle. 4. At each zero crossing the arc momentarily has nothing to sustain it and can be extinguished. 5. A DC current never reaches zero on its own, so the arc has to be blown out by other means. 6. Large breakers add insulating gas and gas jets precisely because arcs are otherwise hard to kill. 7. Option one states the opposite of what alternating means, which is the giveaway. _Source: OpenStax College Physics (CC BY 4.0), Ch 20 "Electric Current, Resistance, and Ohm's Law", section Thermal Hazards_