Hominins have been variably defined scientifically as having which of the following?
a. a large brain, toolmaking abilities, adaptations for bipedalism
b. toolmaking abilities, but no particular biological adaptations for bipedalism
c. a moderately-sized brain, adaptations for quadrupedalism, and biocultural strategies
d. a large brain, toolmaking abilities, adaptations for quadrupedalism
e. a small brain, no toolmaking abilities, and no adaptations for bipedalism