Respuesta :
Answer:
A. always
Step-by-step explanation:
we know that
Parallel lines are those lines which never intersect to each other and always have same distance between them
Two lines always have same distance will only be possible when they lie on same plane
and we know that
same plane means co-planar
so, two lines will be parallel only if they are co-planar
It means that
Parallel lines are always co-planar
So,
Answer is
A. always
