Among the following acids which has the lowest $\text{p}{K}_a$ value?

A lower $\text{p}{K}_a$ value indicates a stronger acid.Alkyl groups are electron-donating ($+I$ effect), which destabilizes the carboxylate anion and decreases acidity.$\text{HCOOH}$ (Formic Acid) has no alkyl group to provide a $+I$ effect, making it the strongest acid in this list.