both a relational database and a NoSQL non$-$relational database. The relational database would help solve the existing problems, and a NoSQL non$-$relational database would help us manage additional data, such as that gathered from social media and web applications, as we continue to grow.

Response $2$ of $4$: a relational database, because it is the most cost$-$effective solution to our current problems. It would help to reduce data redundancy, decrease inconsistency in the data, and also improve data security at the same time.a relational database, because it is the most cost$-$effective solution to our current problems. It would help to reduce data redundancy, decrease inconsistency in the data, and also improve data security at the same time.

Response $3$ of $4$: a NoSQL non$-$relational database, because it's the hottest trend. It will solve our current problems and also allow us to manage more advanced types of data, such as those from web applications, social media, and more.a NoSQL non$-$relational database, because it's the hottest trend. It will solve our current problems and also allow us to manage more advanced types of data, such as those from web applications, social media, and more.

Response $4$ of $4$: a new database developed internally to meet the specific needs we have here at Mendoza$$s Market.a new database developed internally to meet the specific needs we have here at Mendoza$$s Market.