An Analyst Gathered the Following Data for a Company Based Only on the Information Above, the Most Appropriate Conclusion

An analyst gathered the following data for a company: $\begin{array}{lccc}&2013&2014&2015\\\text { Sales } & \$ 5,000,000 & \$ 4,900,000 & \$ 4,770,000 \\\text { Net assets } & \$ 1,630,000 & \$ 1,625,000 & \$ 1,623,000 \\\text { ROE } & 9.8 \% & 10.0 \% & 11.2^{\circ} \% \\\text { Total asset turnover } & 2.0 & 2.1 & 2.2 \\\text { Gross margin } & 33.0 \% & 33.6 \% & 34.2 \%\end{array}$ Based only on the information above, the most appropriate conclusion is that:

A) the company's net profit margin and debt levels have decreased.
B) the company's net profit margin and debt levels have increased.
C) the company's net profit margin has decreased but debt levels have increased.
D) the company's net profit margin has increased and it has more liquidity.