An attacker sits between the sender and receiver and captures the information and re-transmits to the receiver after some time without altering the information. This attack is called as Denial of service attack.
A Masquerade attack is a type of attack where the attacker pretends to be an authorized user of a system in order to gain access to it or to gain greater privileges than they are authorized for.
Data warehouse is subject oriented, integrated, time variant, nonvolatile collection of data in support of management decisions.
Data mining refers to the extraction of useful information from a bulk of data or data warehouses.
Web mining Web mining is the integration of information gathered by traditional data mining methodologies and techniques with information gathered over the World Wide Web.
Database Management System software that handles the storage, retrieval, and updating of data in a computer system.
Explanation : In Data mining, classification rules are extracted from decision Tree, not from database, information or data. So, option (C) is correct.