I have a question about a practice test!! Why is the correct answer A? I choose C. I can't understand it.

Question

These and other problems with the Milankovitch cycles led some researchers to seek alternative explanations for the cyclic arrival of extended ice ages. In the 1990s, it was discovered that the orbital inclination of the Earth to the sun and planets could also be responsible for climate changes. If we imagine a flat plane with the sun in the center and the planets revolving around it, the Earth slowly moves in and out of the flat plane by a few degrees, repeating the cycle every 100,000 years. Two scientists. Muller and MacDonald, have proposed that it is this orbital inclination which is ultimately responsible for the periods of glaciation and warming. They argue that because of the oscillation. the Earth periodically travels through clouds of debris, in the form of dust and meteoroids. Such debris could reduce the amount of solar energy reaching the surface of our planet, thus plunging it into regular cold periods.

 

In paragraph 4, why does the author suggest the image of a flat plane?

A, To help the reader visualize the positions and movements of the heavenly bodies

B, To demonstrate to the reader how the Earth orbits the sun

C, To support the argument that the orbital inclination increases tilting

D, To show how the Milankovitch theory doesn't explain the cyclical changes in climate

Answer 1

Hi Saori;

You chose the answer that there is a connection between "orbital inclination" and "tilting".  There is no connection being discussed.  In the sentence at issue, the author uses the word "imagine".  The answer is A because this connects to the philosophy of helping the reader visualize...