An answer strongly supported by the statements must directly follow from the information given, just as a conclusion would.
We are presented with a few facts:
Pilots record gauge readings at several intervals on each AirMax flight.
The gauge readings on a flight of AirMax Craft 123 were consistent with the pattern of gauge readings observed when an engine is beginning to be dangerously corroded by rust.
Three days after these readings, the plane crashed.
The engine recovered from the craft and displayed a certain amount of rust. This level of rust was not enough, in and of itself, to cause a plane to crash; we know this because it is the same level found in planes that landed successfully.
The level of rust damage on the engine of AirMax Craft 123 is less than the level of rust damage on planes that crash due to rust damage more than a day after gauge readings indicated that the engine was beginning to be dangerously corroded by rust.
Choice C directly follows from the statements. Remember, there are four separate types of plane at play in this argument: planes that show gauge readings that imply the beginnings of serious rust damage (from 2), planes that land successfully (from 4), planes that crashed more than one day after having bad gauge readings (from 5), and AirMax Craft 123 itself. The gauge readings of each of these planes is named in the abstract; let's actually plug in values just to keep track of all the complexities.
There are also two types of reading- engine readings, which are official, and patterns of gauge readings, which are predictive.
Let's say that some planes that land successfully have engines with a level of 48 rust units (whatever those are). That means that AirMax Craft 123's engine must have a comparable level- say, 50 rust units- this comes from point (4). AirMax Craft 123 is also said to have had a pattern of gauge readings that matches that of planes that are beginning to be dangerously corroded by rust. Let's call this a "Code Red" warning. AirMax Craft 123 had a "Code Red" warning, and so do the planes in (2). Thus, a plane with a "Code Red" warning can have an engine with a rust level of 50 three days later.
Now, the fourth entity- the really confusing one: planes that crash from rust damage more than one day after having bad readings. We know that the level of rust damage in the engines of those planes is much higher than in the others (from point 5), so let's call it 80 rust units. This implies that if a plane has a "Code Red", and then crashes after one day or more, a group which COULD include AirMax Craft 123, has a rust level of 80. We know that AirMax Craft 123 did have a "Code Red" and that it did crash; but its actual engine had only 50 rust units. Thus, it is not a member of the group of planes (in 5) that crashed due to rust damage. Choice C is correct.
Choice A is out of the scope of this argument; all that the argument states about a pattern of gauge readings is that the one observed is consistent with one that results when an engine begins to display signs of rust damage. There's no sure indication as to whether the plane's engine was actually damaged at all by anything.
Choice B, again, is out of the scope of the argument; the argument does not actually give the cause of the plane's crash. We only know that the engine's rust level was lower than rust levels observed when a sign indicates that the engine is dangerously corroded.
Choice D does not follow from the statements, which do not even address what the pattern is like on the day that a plane actually crashes.
Choice E makes a claim that is unsupported; the argument only addresses a group of planes that do fly more than a day after a sign indicates that the engine is dangerously corroded by rust. There is nothing stated about how likely it is for planes displaying these signs to crash before a day passes.
Choice C is correct.
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