Show Field values from another table field value without repeated value

[SreeA]

I have a urgent requirement. In table A there are records with field A, field type is String.

value of field A are based on record.

Record            Field A

record 1          Apple

record 2          Bat

record 3          Apple

record 4          Tee

In table B there is a field B with dropdown list values to select. But I want see only field A values with no repeated values.

output:

field B (dropdown list)

apple

bat 

tee