Critical Reasoning

Delta Products Inc. has recently switched at least partly from older technologies using fossil fuels to new technologies powered by electricity. The question has been raised whether it can be concluded that, for a given level of output, Delta's operation now causes less fossil fuel to be consumed than it did formerly. The answer, clearly, is yes, since the amount of fossil fuel used to generate the electricity needed to power the new technologies is less than the amount needed to power the older technologies, provided level of output is held constant.

In the argument given, the two boldfaced portions play which of the following roles?

(A) The first identifies the content of the conclusion of the argument; the second provides support for that conclusion.
(B) The first provides support for the conclusion of the argument; the second identifies the content of that conclusion.
(C) The first states the conclusion of the argument; the second calls that conclusion into question.
(D) The first provides support for the conclusion of the argument; the second calls that conclusion into question.
(E) Each provides support for the conclusion of the argument.

i understood and "clearly answer is yes" is a conclusion and 2nd bold face is part of the conclusion but how come the first boldface support the conclusion.Its just presenting a fact that delta products switch it does not support that this switch saved fuel consumption.its like a background and not a premise
thankyou