Shortly ago, I thought of a new way we could try and find out what the sauropods introduced in X are; given that the DVDs from around that time pushes the now-defunct Jurassic Park Institute so much, perhaps the production used the Jurassic Park Institute as a reference for its sauropod designs.
With this in mind, I made a list of X sauropods and sauropods that I think resemble them to some degree:
With this in mind, without further ado:
Poll wraps up on August 3, vote seriously and don't manipulate it with alts. This is not a "what is this currently identified as?" trivia game.