Only the d examples are correct. The a, b, and c examples are not correct.
The rule for choosing the correct pronoun form is very simple: after a preposition"”and "between" is a preposition"”use the object form.
The object forms of the personal pronouns are
me, you, him, her, it, us, and them.
No matter how many pronouns there are as the object of a preposition, they are always in the objective form.