Assume that we have a relation scheme R$($A$,$B$,$C$,$D$,$E$)$ over which we know the functional dependency AB $->$ BCD holds true. Given this assumption, which of the following statements must also be true?

Group of answer choices

AB $->$ BCDE must also be true.

AB $->$ E must also be true.

AB $->$ ABCDE must also be true.

A $->$ BCD must also be true.

Cannot decide anything about $($a$)-($d$)$ unless we know the primary keys.