The section presents a chemistry problem related to the acidity of different chemical compounds. It asks which of the given options is the weakest acid. The options provided are:

A. HCl (Hydrochloric acid)  
B. \( \mathrm{H}_{2} \mathrm{CO}_{3} \) (Carbonic acid)  
C. \( \mathrm{H}_{2} \mathrm{SO}_{4} \) (Sulfuric acid)  
D. \( \mathrm{HNO}_{3} \) (Nitric acid)  

The key topic is the comparison of the acidity of these acids, with a focus on identifying the one with the weakest acidic properties.