Given that E
is the midpoint of AD¯¯¯¯¯
and BC¯¯¯¯¯
, which of the following proves that AB¯¯¯¯¯∥CD¯¯¯¯¯
?

The figure shows two triangles A B E and E C D with a common vertex E. Points A, E, D lie on one line. Points B, E, C lie on one line.