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In a way; if you choose Plains as the only biome you'll also get Sunflower Plains, Forest, Flower Forest, and Forest Hills since the game adds these in a separate step after choosing the parent biome and Mojang did not consider that when they added the single biome option (this is considered to be a bug). Many other biomes also have at least one variant, even if just hills, and you'll have rivers in most cases (these can be "disabled" by editing the preset string to set the size (spacing) to a very high value; 20 gives an average spacing of over 16 million blocks while not making them wider). Some variants cannot be obtained unless you specifically choose them, such as Jungle Edge, since that requires that a jungle borders another biome that is not a sub-biome within it.
Also, you can determine which biomes are sub-biomes of another biome with AMIDST since they appear as smaller patches within normal-sized biomes; I've seen plains with all four "variants" in a single biome.