Multiple selections from same pull down field
I am new to database creation, but am trying to create a database with pull down fields that I have populated with custom created list. I have some pull down fields in which I would like to be able to select more than one choice. Is there a simple way to allow this?
eg. Choices are A, B, or C. But sometimes the field could be A and B, A and C, or A and B and C.
I know the simple way would be to create all the options in the custom list, however some of the lists might have 40-50 choices which would quickly complicate the list.
Thanks for any advice.