Which of the following statements are correct?
1. When marginal revenue is positive, total revenue increases with increase in output. 2. When marginal revenue is zero, total revenue is maximum. 3. When marginal revenue becomes negative, total revenue falls with increase in output.
Select the correct answer using the code given below:

Options

A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2 and 3