The T. urticae mite is an agricultural pest that feeds on many crop

Question

The T. urticae mite is an agricultural pest that feeds on many crop plants, including tomatoes. Some tomato farmers manage this threat by introducing the G. occidentalis mite, a predator of T. urticae. Other tomato farmers spray their crops with miticide, killing all mites within the area that is sprayed.

If the statements above are true, which of the following must be true?

(A) Only if G. occidentalis has first been introduced into a tomato field will spraying with miticide eliminate all T. urticae from the field.
(B) The introduction of G. occidentalis and spraying with miticide are the only two known methods for controlling an outbreak of T. urticae on a tomato farm.
(C) If live N. californicus mites are found in a field that has been sprayed with miticide, these mites entered the field sometime after the field was sprayed.
(D) T. urticae causes more economic damage to tomato farmers than it does to growers of any other major crop plant.
(E) Some tomato farmers have tried both introduction of G. occidentalis and spraying with miticide as ways of managing the threat posed by T. urticae.

LamboWalker · Answer

'T' mites damage many crops, including tomatoes. Farmers have found two ways to deal with T mites :
1. Introduce 'G' mites into the fields and watch these mites devour T mites.
2. Spray the field with miticide, which kills all types of mites.
We are asked to find what must be true based on this argument.

(A) Only if G. occidentalis has first been introduced into a tomato field will spraying with miticide eliminate all T. urticae from the field. 
Not at all what the argument is saying.

(B) The introduction of G. occidentalis and spraying with miticide are the only two known methods for controlling an outbreak of T. urticae on a tomato farm. 
'Only' is an extreme word. We don't know from the argument whether these are the only two methods. There could be more.

(C) If live N. californicus mites are found in a field that has been sprayed with miticide, these mites entered the field sometime after the field was sprayed. 
Funnily enough, the introduction of a new type of mite might make this option seem out of scope. But since we know that miticide kills all types of mites, this is the only option which correctly gives a statement this is 100% true based on the argument. Correct answer.

(D) T. urticae causes more economic damage to tomato farmers than it does to growers of any other major crop plant. 
Can't say this from the argument.

(E) Some tomato farmers have tried both introduction of G. occidentalis and spraying with miticide as ways of managing the threat posed by T. urticae 
We cannot be 100% certain whether there are any farmers that have tried BOTH methods from the argument.

Answer is  (C)

Btw, may I know the source of this question? Thanks.

mrfrantic · Answer

It's taken from BT Methods sample admission test paper ( Link )

whatsarc · Answer

(A) Only if G. occidentalis has first been introduced into a tomato field will spraying with miticide eliminate all T. urticae from the field.  (Nowhere mentioned) Incorrect 
(B) The introduction of G. occidentalis and spraying with miticide are the only two known methods for controlling an outbreak of T. urticae on a tomato farm.  They are the two methods, not the only two. Incorrect.

(C) If live N. californicus mites are found in a field that has been sprayed with miticide, these mites entered the field sometime after the field was sprayed.  After spraying any mite can come and wont be killed. Makes sense, Correct.

(D) T. urticae causes more economic damage to tomato farmers than it does to growers of any other major crop plant.  This could be true, not must be true. Incorrect 
(E) Some tomato farmers have tried both introduction of G. occidentalis and spraying with miticide as ways of managing the threat posed by T. urticae. Some farmers tried introduction of G.o and others tried the spray.  We cant deduce anything out of it, can't say some tried both cant say some tried none. Incorrect

VerbalBot · Answer

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The T. urticae mite is an agricultural pest that feeds on many crop

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The T. urticae mite is an agricultural pest that feeds on many crop

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