In Spanish:
* La aula: This is the most common and general form, used in most of the Spanish-speaking world. It uses the feminine definite article "la" because "aula" is a feminine noun.
* El aula: This is a less common variant used in some parts of Spain, particularly in the Andalusian region. It uses the masculine definite article "el" due to a regional linguistic variation.
In Portuguese:
* A aula: This is the correct form in Portuguese, using the feminine definite article "a" because "aula" is a feminine noun.
In other languages:
The definite article for "aula" may vary depending on the specific language. It's important to check the grammar rules of the language you are using.
In conclusion:
The most common and general definite article for "aula" is la in Spanish and a in Portuguese. However, some regional variations may exist.