Answer: My best guess would be B but i might be wrong that sounds most right to me. :)
Explanation:
A) Cellular respiration. Source: I'm a Biology teacher. ;)
Answer:
Velocity
Explanation:
Given the change in positive (direction) over time we are given the velocity formula.
V = Change in direction/Change in time
Since we are given a direction we can rule out speed as well as direction in itself. We can also rule out acceleration because that is the change in Velocity divided by change in time.