drop list to another drop list

i need to make a drop down list selection in one cell to set the criteria in another cell's drop down list.
example...

A1 list is 1,2,3, & 4.
if i select 1, then B1 list should be A, B, C, & D.
if i select 2, then B1 list should be E, F, G, & H. and so on.

can anyone help me with this.
thank you.

once i posted this, it showed me exactly what i was wanting to do. i spent 30 min. looking for it but couldn't find it, now i did. thank you for looking anyway.