Space rockets that are used to launch satellites into orbit protect

Since this question was bumped up and caught my eye, I thought I would take the time to share my thoughts, in hopes that someone else may find them useful.


To support the conclusion, it is necessary to understand that conclusion and follow the linear logic of the passage. The conclusion is easy to spot here, since we have a conclusion-trigger in the transition therefore. What is that conclusion? Engineers should use Tungsten Carbide for engine encasing instead of Titanium so that rocket engines are better protected. There are a few premises brought up in the passage by way of comparisons between Titanium and Tungsten Carbide:

(1) Tungsten Carbide is four times harder than Titanium
(2) Tungsten Carbide is considerably more resistant to G forces and heat than Titanium

Such comparisons would be irrelevant if not applicable to the background information provided earlier in the passage. But those bases are covered in the first sentence. Space rockets protect engine components from violent turbulence and G forces, so (2) above is pertinent, and this protection comes about by encasing [the engine components] in hard metals, so (1) above is also pertinent. With these premises in mind, we need to find an answer that speaks to the conclusion from earlier.

Analysis: Great. Tungsten Carbide has yet another use, and the keyword protection is on display, but then we get the bit about space suits. As awful as it may sound, we are not concerned with protecting astronauts, but with protecting vital engine components. This answer falls outside the scope of the conclusion. Red light.

Analysis: We do not want problems associated with Tungsten Carbide. In fact, we are looking for quite the opposite, to support a conclusion that calls for a switch from Titanium to Tungsten Carbide. Get rid of this reversal. Red light.

Analysis: Again, this is of marginal interest, but whether Tungsten Carbide is or is not currently being used in any sort of capacity is irrelevant to the conclusion. The conclusion is concerned with protecting engine components, not with how practical a switch to Tungsten Carbide may be. Red light.

Analysis: This answer falls into the same camp as (A). You almost feel as if a Tungsten Carbide salesman is giving you his pitch: "But wait, there's more!" Notice that scratch-resistance is not mentioned in the conclusion, nor is it mentioned anywhere else in the passage. This distraction is for the test-taker who picks up on the word resistant and runs amok with it. Red light.

Analysis: Sometimes I get a little nervous upon eliminating the first four choices, hoping that that last answer just leaps off the screen at me. (The red-yellow-green-light method I use helps me avoid running back through all the answers if such a last choice fails to get the green light.) In this case, my concerns were allayed the moment I laid eyes on this option. The keyword protection is back, only this time it correctly ties into turbulence from line 1 of the passage and tensile strength from the second line of the passage. If Tungsten Carbide offers better protection for whatever it is encasing from both turbulence and impacts, then it is easy enough to see how this new information would support the conclusion drawn. Green light.

I hope that helps the community.

- Andrew