The North American frontier changed some of the characteristics of the pioneers of the 175
The entire assets of one of these huge families often amounted, in the beginning, to little more than an axe, a hunting knife, an auger, a rifle, a horse or two, some cattle and a few pigs, a sack of seed com and another of salt, perhaps a crosscut saw, and a loom. Those who moved first into a new region lived for months at a time on wild meat, Indian maize, and native fruits in season. Yet if they were poor at the beginning, they confidently expected that soon they would be rich.
In a way almost impossible to define to urban dwellers, a slice of ground suitable for farming represented not just dollars and cents, but dignity. The obsession brought shiploads of yearners (渴求者) every week to Boston, New York, Philadelphia, Baltimore, Charles Town and Savannah. It sent them streaming westward into the wilderness after their predecessors to raise still more children who wanted still more land.
What kind of stylistic device did the author use in the phrase "as pine roots cracking granite to grow"?
A.Metaphor.
B.Simile.
C.Personification.
D.Imagination.