Earth's magnetic field

[MCapri]

Which of the following best completes the passage below?
Monarch butterflies, whose average life span is nine months, migrate from the midwestern United States to selected forests outside Mexico City. It takes at least three generations of monarchs to make the journey, so the great-great-grandchildren who finally arrive in the Mexican forests have never been there before. Yet they return to the same trees their forebears left. Scientists theorize that monarchs, like homing pigeons, map their routes according to the earth’s electromagnetic fields. As a first step in testing this theory, lepidopterists plan to install a low-voltage transmitter inside one grove of “butterfly trees” in the Mexican forests. If the butterflies are either especially attracted to the grove with the transmitter or especially repelled by it, lepidopterists will have evidence that______
(A) monarch butterflies have brains, however minuscule
(B) monarch butterflies are sensitive to electricity
(C) low-voltage electricity can affect butterflies, whether positively or adversely
(D) monarchs map their routes according to the earth’s electromagnetic fields
(E) monarchs communicate in intergenerationally via electromagnetic fields.

Please provide explanation as well...

[sushen.kumar]

I think it should be D, as the experiment is intended to test whether "butterflies map their routes according to the earth’s electromagnetic fields or not".
What is the Official Answer?
Any other explaination to it.

[itsme_sanket]

Imo B

[sushen.kumar]

Imo B

@Sanket can you explain your perception.

[Lhomme]

Imo B

I agree with sanket. It should be B

as a first step in testing this theory, lepidopterists plan to install a low-voltage transmitter inside one grove of “butterfly trees” in the Mexican forests. If the butterflies are either especially attracted to the grove with the transmitter or especially repelled by it, lepidopterists will have evidence that
This is just the first step. hence they cannot come to the conclusion right away. It will have to be in steps. B is the only possible choice.

[itsme_sanket]

(A) monarch butterflies have brains, however minuscule - out of context we are not sure
(B) monarch butterflies are sensitive to electricity - correct because simple
(C) low-voltage electricity can affect butterflies, whether positively or adversely - may be it is possible no effect
(D) monarchs map their routes according to the earth’s electromagnetic fields - first step and in first step final thing cannot be proved
(E) monarchs communicate in intergenerationally via electromagnetic fields. - illogical..

[HD205]

What is the correct answer?
I've already read the article about monarch butterflies on wikipedia, but I have found nothinng about this. Here is the link: Monarch (butterfly) - Wikipedia, the free encyclopedia .

[prabhu3645]

Which of the following best completes the passage below?
Monarch butterflies, whose average life span is nine months, migrate from the midwestern United States to selected forests outside Mexico City. It takes at least three generations of monarchs to make the journey, so the great-great-grandchildren who finally arrive in the Mexican forests have never been there before. Yet they return to the same trees their forebears left. Scientists theorize that monarchs, like homing pigeons, map their routes according to the earth’s electromagnetic fields. As a first step in testing this theory, lepidopterists plan to install a low-voltage transmitter inside one grove of “butterfly trees” in the Mexican forests. If the butterflies are either especially attracted to the grove with the transmitter or especially repelled by it, lepidopterists will have evidence that______
(A) monarch butterflies have brains, however minuscule
(B) monarch butterflies are sensitive to electricity
(C) low-voltage electricity can affect butterflies, whether positively or adversely
(D) monarchs map their routes according to the earth’s electromagnetic fields
(E) monarchs communicate in intergenerationally via electromagnetic fields.

Please provide explanation as well...

I think the answer that is logical is D. Low voltage transmitter should generate an electromagnetic field and not just electricity and the scientists are basically trying to prove that the monarch butterflies are sensitive to electromagnetic field and not just electricity. Hence, my choice would be D.

[MCapri]

Official Answer is B