#1 phospholipids and hydrophobicity

It is 10-14 question from MBoC:PB. It is a bit jokey, but raises different physical and biophysical problems about energy, forces and so on.

Five students in your class always sit together in the front row. This could be because (1) they really like each other or (2) nobody else in your class wants to sit next to them? Which explanation holds for the assembly of a lipid bilayer? Explain your answer. If the lipid bilayer assembled for the opposite reason, how would its properties differ?

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Main property of phospholipids is that they are amphiphatic molecules: they have hydrophobic tails and hydrophilic heads. Consequently, molecules – when crowded – try to hide tails away from water and the only way to do that is to get to the water surface (and swing tails into the air) or form vesicle (bubble), where tails are hidden inside. That is tails are forced to get away from water.
So, I suppose, the right answer is (2): every one in the class force them to get on the "surface" of class (in our case it is water).
If phospholipids liked each other, then, I think, no molecules (proteins) could stay inside membrane or among lipids.

Lets check the right answer from the CD, that supply the book.

Lipid bilayers assemble because the surrounding water molecules exclude
the component lipids; thus, analogy (2) is the correct one. If bilayers formed
because of attractive forces among the lipids—analogy (1)—the properties
of the bilayer would likely be quite different. Molecules ‘attract’ one another
by forming specific bonds that hold them together. Such bonding among
lipids would make the bilayer less fluid, perhaps even rigid, depending on
the strength of the interaction.

I was quite right, except forces approach. But yes, attracted molecules are more durable system, no molecules can intercept it or destroy. So my idea on proteins is also right.