The span was so long, the height so great, and the enterprise likely to be so costly, that few thought of it as something begun in earnest. . . . But Science said, "It is possible," and Courage said, "It shall be!" . . . . And so this Bridge is a wonder of science. —Opening Ceremonies of the
New York and Brooklyn Bridge,
Seth Low

Which phrase from the excerpt is a fact that supports the opinion that the bridge is “a wonder of science”?

A. “the span was so long, the height so great”
B. “Science said, ‘It is possible’”
C. “something begun in earnest”
Can you please explain it and not just give the answer strait up so I can understand. Thank you!