Which pairs of angles are congruent because they are vertical angles? check all that apply.

a. < 1 and < 4
b. < 14 and < 12
c. < 7 and < 8
d. < 10 and < 8
e. < 3 and < 5
f. < 8 and < 12

B, D represent pairs of vertical angles.
___
Other pairs may be congruent, but they are not vertical angles. The lines that look parallel must be assumed to be NOT parallel, because they are not marked in the diagram as being parallel. Thus ∠8 ≠ ∠12, for example.