In a certain reaction, 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours, and so on. Dimension of the velocity constant (rate constant) are:

a) hour⁻1
b) mol litre⁻¹hour⁻¹
c) litre mol⁻¹ sec⁻¹
d) mol sec⁻¹