I agree with Ian. The key here is to see what is linked.
Main: Hit rhodopsin ====> Retina Light is registered
Sometimes: Rhodopsin changes chape ======> Retina Light registered [ error in visual system]
The goal is for Retina to display the visual system based on what is hitting rhodopsin (the pigment). If nothing is hitting Rodhopsin and it's registering on the Retina, it's going to be an error in the visual system.
The degree that the "sometimes" situation occurs is LINKED to temperature.
We know it's linked...the question is whether knowledge of this link supports (B) or does not support (B).
(B) says the visual system is more error prone temperatures are HIGHER.
Steven is right that there is no link whether up or down is DIRECTLY linked to the visual system being more error prone. But that does not matter. If the statement were made in the opposite state, that would also be supported. It's just a matter of degree to which the passage can support that statement.
So either direction that is made (whether B or the opposite of B), it would still be a conclusion that is supported by information in the passage? Why? Because if you ask the challenge question, how is it that we know that "Higher Temperature" = More Error, it's because Temperature and Error are Linked.
As you can see, we answered the challenge question...we might not have answered it in complete detailed but the first step is to show that they are linked. A stronger support would be to give a specific direction. They are simply different degrees of support.
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