A student makes a graph of initial rate vs. concentration in order to determine the order of a reaction. If the reaction is first order, what would she see on the graph?

a) a straight, horizontal line at the initial rate
b) a straight line slowly going down to zero
c) a straight line beginning at the origin and gradually increasing
d) a curved line showing an increase in rate
e) a curved line showing an decrease in rate

c) a straight line beginning at the origin and gradually increasing