If you don't have the other comments and information, I could see how you might interpret it differently.
However, at M4Carbine.net, it was pretty much a "given" detail/variable. So A=C was in the word portion of the problem.
That is why the OP wrote it the way he did.
When giving a source by itself that is dependent on "given" information established at another location, it might be a good idea to also link that information.
Know the status of your weapon
Keep your muzzle oriented so that no one will be hurt if the firearm discharges
Keep your finger off the trigger until you have an adequate sight picture
Maintain situational awareness