Scenario 8:MA store is an online clothing retailer founded in 2010.

Scenario 8:MA store is an online clothing retailer founded in 2010. They provide quality products at a reasonable cost. One thing that differentiates MA store from other online shopping sites is their excellent customer service.

MA store follows a customer-centered business approach. They have created a user-friendly website with well-organized content that is accessible to everyone. Through innovative ideas and services, MA store offers a seamless user experience for visitors while also attracting new customers. When visiting the website, customers can filter their search results by price, size, customer reviews, and other features. One of MA store's strategies for providing, personalizing, and improving its products is data analytics. MA store tracks and analyzes the user actions on its website so it can create customized experience for visitors.

In order to understand their target audience, MA store analyzes shopping preferences of its customers based on their purchase history. The purchase history includes the product that was bought, shipping updates, and payment details. Clients' personal data and other information related to MA store products included in the purchase history are stored in separate databases. Personal information, such as clients' address or payment details, are encrypted using a public key. When analyzing the shopping preferences of customers, employees access only the information about the product while the identity of customers is removed from the data set and replaced with a common value, ensuring that customer identities are protected and cannot be retrieved.

Last year, MA store announced that they suffered a personal data breach where personal data of clients were leaked. The personal data breach was caused by an SQL injection attack which targeted MA store’s web application. The SQL injection was successful since no parameterized queries wereused.

Based on this scenario, answer the following question:

What did MA store use when storing clients' address and payment details in its system?