Question

passage
joe balo at oregon state university and his collaborators used a scanning electron microscope combined with spectroscopy to examine the scales on the california king snakes underbelly. that analysis showed fatty lipid molecules lining up in regular rows and columns, perpendicular to the scales. this, apparently, is why the snakes outer lipid layer is so tough. it acts like the nylon layer of a down - jacket, preventing friction - inducing particles from touching the underlying skin, while still being flexible enough not to break.
the scales on a snakes back are thicker, but have a thinner lipid layer, and thus are less able to switch from soft to stiff. “the back scales are mainly there to prevent reflections, and provide camouflage, rather than help with movement,” said collaborator stanislav gorb at university of kiel in germany.
you cant feel those subtle differences with your bare hands, but they are there, nonetheless. and those slight changes in structure could lead to extra - slippery paints and coatings, the next generation of engines, or robotic snakes designed to worm their way into tight spaces.
“anything that is sliding needs to reduce friction,” said gorb. and the california king snake is a master of that.
adapted from jennifer ouellette, “this is what gives the king snake its slither.” ©2015 by gizmodo.
question
which of the following conclusions about the california king snakes lipid layer can most reasonably be drawn from the passage?
the scales on the belly of a california king snake are lined up so closely together that they provide a barrier between the snake and the ground it moves across.
the fatty lipid molecules that coat the california king snakes skin offer more assistance reducing friction on the snakes underbelly than on its back.
the scales on the back of a california king snake are covered with a thin layer of fatty lipid molecules to assist with camouflage.
manufacturers have designed outerwear based on what biaos research revealed about the california king snakes outer lipid layer.

Explanation:

The passage states that the California king snake's underbelly has fatty lipid molecules in regular rows and columns, which helps reduce friction, and the back scales have a thinner lipid layer and are mainly for camouflage. This implies that the lipid - molecules on the underbelly are more effective in reducing friction. Option A is not about the lipid layer. Option C misattributes the function of the lipid layer on the back (it's mainly for camouflage not directly related to the lipid - layer's role in assisting camouflage). Option D has no support in the passage as there's no mention of manufacturers designing outerwear.

Answer:

B. The fatty lipid molecules that coat the California king snake's skin offer more assistance reducing friction on the snake's underbelly than on its back.