According to the article, why did scientists create petrochemicals?
A. Because rubber from plants harmed the environment
B. Because they were worried about the environment
C. Because the U. S. didn't have enough rubber
D. Because World War II had just started

What is implied in this sentence from mark twain's "the ? 1,000,000 bank-note"? i was puzzled, and wanted to discuss the matter a little further, but they didn't; so i took my leave, feeling hurt and insulted to be made the butt of what was apparently some kind of a practical joke, and yet obliged to put up with it, not being in circumstances to resent affronts from rich and strong folk.