Either form of “ID / IDs” to open ...

Hello, everyone,

Choose the suitable answer in following blank;

“You can submit ________ form of ID to open your new account at the bank.”

1) both, 2) these, 3) some, 4) either

While the answer is suggested as no.4) in my text book, I don’t think the suitable one is available in the above shown with following reasons – especially, we should treat the “Identification” as a countable noun in this context and also I think the one suitable ID would be enough to open our new account at the bank;

1) to be the answer, it should read, “You can submit both form<s> of ID<s> to open ~ .”

2) to be the answer, it should read, “You can submit these form<s> of ID<s> to open ~ .”

3) to be the answer, it should read, “You can submit some form of ID to open ~ .”

4) to be the answer, it should read, “You can submit either form of ID<s> to open ~ .”

In 4) I still think the “ID” should read as “IDs”.

Will much appreciate if you propose with the correct answer with some explanation.