Can a Dynamic Drop down reuse an option?

I have added a dynamic drop down? Can the dynamic drop reuse the same option multiple times based upon the parent?

For example:
We have a drop down test_type_c with options a,b,c,d
There is a dynamic dropdown test_dd_c with a parent of test_type_c
We would like to have an drop down choice of “Other” do I need to define it as

a_other
b_other
c_other
d_other

Is there a way to say _other?
or a_b_c_d_other?