A firm's total asset turnover increased from 0.75 to 0.90. Which of the following is true about the given data?

Select one:

a. Its assets have been efficiently used to derive the optimum level of net income.

b. Its assets have been efficiently used to derive the optimum level of sales.

c. Its assets have been efficiently used to derive the minimum level of gross profit.

d. Its assets have been efficiently used to derive the minimum level of net income.