This natural arch was produced by:
a. heavy exposure to running water at the base of the rock.
b. erosion of softer minerals from the center of the rock.
c. excessive weathering caused by heat and pressure on top of the rock.
d. repeated exposure to wind on the lower parts of the rock.

The many stone tools, fragmentary animal bones, and teeth found at gran dolina, spain, indicate that hominids there? a. processed and consumed animals and other hominids. b. did not differ appreciably from earlier asian homo erectus. c. were similar to later homo sapiens. d. none of the above