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# Mouse-2002, 23 bytes

??"A"["B"|"C"["D"|"E"]]


Switches on two inputs, which each should be either 0 for false or anything else for true.

Ungolfed, as a function:

#Y,?,?;

$Y 1% a: 2% b: "A" a [ "B" | "C" b [ "D" | "E" ] ]$


Brackets just test if the top of the stack is true, and | is else.

This is a translation of @Cᴏɴᴏʀ O'Bʀɪᴇɴ's ES6 answer.