Our Ancestors Were Bipedal by at Least _____ Million Years

Question

Our ancestors were bipedal by at least _____ million years ago, as evidenced by the Lucy skeleton.
A)1)2
B)2)4
C)3)2
D)4)5

Accepted Answer

The Lucy skeleton is estimated to be 3.2 million years old, which means that our ancestors were bipedal by at least 3.2 million years ago.