Which of the following is a typical use of data mining?

• A. Cross-selling
• B. Data backup
• C. Hardware maintenance
• D. Email filtering

Answer: (A)

Data mining is about uncovering patterns and relationships in large data sets to support decisions and actions. A typical use is cross-selling: by analyzing what customers buy together, the system can recommend additional products to a buyer, increasing the chance of extra purchases. This relies on techniques such as association rules or market basket analysis to discover product pairs that often appear together, turning those patterns into actionable recommendations when a customer shows interest in one item.

Data backup focuses on preserving copies of data for recovery, not extracting patterns. Hardware maintenance is about keeping IT infrastructure running, not deriving customer insights from data. Email filtering classifies messages to separate spam from legitimate mail, which is a different kind of data-driven task and not the primary business use of data mining aimed at boosting sales.