42) A firm has increased its return on assets (RDA) from the prior period. The firm's return on sales increased signicantly and its total asset turnover decreased a fair amount over the period. Which of the following is the correct conclusion from these results? a. All of the ratios mentioned show that both efficiencyr and effectiveness have increased regarding cost control and asset usage. b. The firm should look for areas where their investment in assets could be reduced to increase measures such as cash turnover. c. The firm should increase control over operating costs by increasing its investment in fixed assets relative to current assets. d. The firm should focus on measures such as gross and operating prot margin as a means to increase total asset turnover