About how long does it take for the reaction to reach equilibrium in this concentration versus time graph?

a graph of reactant and product concentration vs. time; a red curve shows the reactant concentration decreasing while two blue curves show the product concentration increasing with time; both blue curves intersect the red curve; the chemical equation is water reacting to produce hydrogen and oxygen

A.
0.5 second
B.
1.5 seconds
C.
2.5 seconds
D.
4.5 seconds