The "KUVA" fabric, produced by American Synthetics, Inc., was once thought to be a miraculous invention because it was so strong and durable. However, industrial accidents over the past three years have proven that the material is highly flammable (i.e., it catches fire and burns easily). This discovery was very bad news for manufacturers who use the "KUVA" fabric in their products. The weaker fabrics they had been using before caused many of their products to fail; the "KUVA" fabric provided an excellent alternative. Now that they can't use the "KUVA" fabric anymore, manufacturers will have to eliminate all American Synthetics materials from their inventories.
Which of the following assumptions best justifies the author's conclusion?
A. Early tests showing that the "KUVA" fabric was safe now appear to have been incomplete.
(A) is incorrect. The author's conclusion is that manufacturers now have to eliminate all materials made by American Synthetics, not just KUVA, from their inventories. This is obviously an unwarranted conclusion unless all American Synthetics products are dangerous, but there's no evidence here that anything they make other than the KUVA fabric is dangerous. Whether the tests of the KUVA fabric were incomplete is irrelevant; the issue is whether the fact that the KUVA fabric is unsafe renders ALL American Synthetics products unsafe. It doesn't, unless they all contain the KUVA material.
To use an historical corollary, the Ford Pinto automobile of the 1970s was infamous for having a tendency to explode when hit in the rear. The fact that the Pinto was unsafe did not mean that ALL Ford vehicles were unsafe. If crash tests on the Pinto had turned out to have been incomplete, it might reflect poorly on Ford, but would not require all Ford owners to get rid of their cars, or for dealers to stop selling all Ford models.
B. There have been more industrial fires in plants that use the "KUVA" fabric than in those that don't.
(B) is incorrect because it is irrelevant. The issue in the author's conclusion is not the KUVA fabric, it's ALL American Synthetics fabrics. Again, the fact that KUVA is unsafe does not mean that all American Synthetics products are unsafe.
C. The "KUVA" fabric is not as strong or durable as originally believed.
(C) is incorrect because it is not only irrelevant but calls attention to the wrong property of the fabric. It's lack of strength or durability was not what made it unsafe; its flammability did that. Still, as mentioned repeatedly, KUVA itself is not the issue.
D. All materials made by American Synthetics contain some form of the "KUVA" fabric.
(D) is correct.
E. Manufacturers will probably be sued by people who have been injured in accidents caused by products containing the "KUVA" fabric.
(E) is incorrect even if it is probably true. Even if you argue that manufacturers would drop all American Synthetics products in retaliation for such suits, the cause would be too indirect to support the author's specific conclusion.