Here's why:

* Carboxylic Acids: These organic compounds contain the carboxyl group (-COOH). This group has a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group (-OH).

* Anthranilic Acid: Its structure contains a carboxyl group (-COOH) along with an amino group (-NH2).

Therefore, the presence of the carboxyl group makes anthranilic acid a carboxylic acid, despite also having an amine group.