y = ax + b
If "a" of two lines are equal, they are parallel
If "a" of two lines are the opposite inverse, they are perpendicular
As we have:
y = 3x + 2
y = -3x - 1
To be parallel both need to be 3, they aren't
To be perpendicular one of them should have a being the opposite inverse
Opposite inverse of 3 = -1/3
So they aren't perpendicular too.
Option neither.