Which of the following is a disadvantage of a centralized database ?

A centralized database stores all data in a single location, which simplifies management but introduces significant risks. The primary disadvantage is that it creates a single point of failure; if the central server crashes or suffers network issues, the entire system becomes inaccessible to all users. This contrasts with distributed systems where redundancy ensures continuity.\nOption A is incorrect because while centralized access can enhance security through strict controls, it is not inherently a disadvantage. Option B describes an advantage, as centralized databases typically ensure real-time consistency across all records without complex synchronization. Option D is also an advantage in some contexts, though scaling a single server has limits compared to distributed architectures. Ultimately, the vulnerability of relying on one central node makes Option C the correct answer regarding disadvantages.