Problem: Choose the best explanation for how it was possible to "watch" the evolution of E. coli in 11 days.
A. Bacteria can divide rapidly, in as few as 20 minutes.
B. Because bacteria divide very slowly, it is possible to observe change in just 11 days.
C. Because a single bacterium is easily visible to the naked eye, it is easy to observe changes in as little as 11 days.
D. Because bacteria seldom evolve and largely remain unchanged, it is easy to observe the smallest of changes in just 11 days.