Critical Reasoning

The basic ingredients from which cement is made are both cheap and plentiful. Materials as common as limestone and clay will do. Nevertheless, the price of cement is influenced by the price of oil, because turning the basic ingredients into cement in high-temperature kilns uses large amounts of energy.

Which one of the following can be logically inferred from the passage?

(A) Oil is one of the basic ingredients that make up cement.
(B) Oil is a source of energy for some of the kilns used in the making of cement.
(C) The higher the price of cement rises, the higher the price of clay rises.
(D) Whenever oil prices rise, cement prices drop.
(E) A given amount of cement costs no more than the total cost of its basic ingredients.

OA ....

IMO B

You are right

beatthegmatinsept wrote:IMO B

This is another one that is susceptible to the denial test. If you deny B - you say oil is not used as an energy source for the kilns, then oil prices would have no effect on the price of cement and the argument would fail.

Tani Wolff - Kaplan wrote:This is another one that is susceptible to the denial test. If you deny B - you say oil is not used as an energy source for the kilns, then oil prices would have no effect on the price of cement and the argument would fail.

But is this not right that B is mentioned in the argument?

The argument says the price is influenced by the price of oil and then it says turning basic ingredients into oil takes energy - the missing assumption is that oil provides that energy.

Answer is B:

The important thing to note in this sentence is that it says -
"Nevertheless, the price of cement is influenced by the price of oil, because turning the basic ingredients into cement in high-temperature kilns uses large amounts of energy. "

It does not say that Oil is used or coal is used. It just says that it needs a large amount of energy. So some kilns might use coal, nuclear energy, oil etc. So only B addresses that statement -

"Oil is a source of energy for some of the kilns used in the making of cement."

In option B, should "SOME of the kilns" not be a cause of concern? If only some of the kilns run on oil then it's not necessary for price of cement to depend directly on oil (assuming other kilns use different sources of energies)? Please advise.

prakhag wrote:In option B, should "SOME of the kilns" not be a cause of concern? If only some of the kilns run on oil then it's not necessary for price of cement to depend directly on oil (assuming other kilns use different sources of energies)? Please advise.

@prakhag :
This is a inference question and in such questions i believe that even if the answer choice is a representation of a broader aspect mentioned in the argument, then the answer choice is in contention.

In this case,B says "SOME" whereas it is like a generalization in the argument. Hence "SOME" is a representative of the all the kilns.

Hope this helps.

why E is wrong. It says given amount of cement will always be costly then the amount of ingredients in it.

goyalsau wrote:why E is wrong. It says given amount of cement will always be costly then the amount of ingredients in it.

Actually, E says that cost of cement will always be less than equal to cost of ingredients. Oil is not an ingredient but is used to power kilns that produce cement. The cost of oil is going to add up to the cost of cement. Therefore, cost of cement = cost of ingredients + cost of oil + etc (labor,..)