Stella Ltd$.$ has provided you with the following selected information from $2020$ and $2021$: $20212020$ Sales $$785,000$ $$740,000$ Sales returns and allowances $55,20052,000$ Cost of goods sold $358,000305,000$ Operating expenses $285,000255,000$ Profit $86,800128,000$ Using a vertical trend analysis with net sales as a base, which of the following most accurately depicts the information stated above? Select one: A$.$ Profit as a percentage of net sales did not change significantly from $2020.$ B$.$ Profit as a percentage of net sales decreased by $6\mathrm{.}7$ percentage points. C$.$ Cost of goods sold as a percentage of net sales decreased by $5$ percentage points. Cost of goods sold as a percentage of net sales remained consistent from $2020.$