Final answer:
The correct answer is 3) 10. A semi-automatic centre-fire rifle may legally have up to 10 cartridges in its magazine.
Step-by-step explanation:
The correct answer is 3) 10. A semi-automatic centre-fire rifle may legally have up to 10 cartridges in its magazine. In the context of firearms and gun laws, a semi-automatic rifle is a type of gun that fires one round with each pull of the trigger, automatically reloading the next round from the magazine. Unlike fully automatic rifles, semi-automatic rifles are designed to fire one round per trigger pull without the need for manual reloading. The limit on the number of cartridges in the magazine helps regulate the capacity of the rifle to avoid excessive firepower. Some countries may have different limits, but in this case, the legal limit for a semi-automatic centre-fire rifle is 10 cartridges.