Comprehension:
The two plots below show data for four companies code-named $A, B, C$, and $D$ over three years - $2019, 2020$, and $2021$.
The first plot shows the revenues and costs incurred by the companies during these years. For example, in $2021$, company $C$ earned Rs.$100$ crores in revenue and spent Rs. $30$ crores. The profit of a company is defined as its revenue minus its costs.
The second plot shows the number of employees employed by the company (employee strength) at the start of each of these three years, as well as the number of new employees hired each year (new hires). For example, Company $B$ had $250$ employees at the start of $2021$, and $30$ new employees joined the company during the year.
The ratio of a company's annual profit to its annual costs is a measure of its performance. Which of the four companies had the lowest value of this ratio in $2019 ?$
- Company $\mathrm{C}$
- Company $\mathrm{A}$
- Company $\mathrm{B}$
- Company $\mathrm{D}$