Which of the following statements is correct for the first-order reaction: A 2B?

Which of the following statements is correct for the first-order reaction: A 2B? a. The concentration of A decreases linearly with respect to time. b. The concentration of A is constant with respect to time. c. The rate constant, k, of the reaction decreases linearly with respect to time. d. The rate of reaction is constant with respect to time. e. The natural logarithm of the concentration of A decreases linearly with respect to time.