How to setup laser for shooting?

[Bmr4life]

I just mounted a under barrel laser on my gun. Which of these am I supposed to do?

A) Adjust the laser so it is parallel with bullet travel and always aim with the laser just beneath my target since the bullet will hit above where the dot is?

B) Adjust the laser so it will cross with the bullet path at the distance I shoot at most of the time? Example, angle laser up so it will meet where the bullet will go at 7 yards. But if I shoot at 15 yards, the bullet will go underneath the laser spot since the laser has crossed and gone above the bullets travel???

Thanks.

[8541/9999]

First figure out the mission of the laser Plinking on the range or Self Defense. Dont say both your weapon may have more than one mission but the laser needs to be dedicated for one mission.
How close is the laser to the center of the bore? how secure is your mount?
Waht weapon is it mounted on? What range will you be engaging targets at with this laser?