Statement 1 is correct: Blockchain is a distributed, transparent, secure, and immutable database. It’s records are accessible across a network, making them visible to relevant stakeholders while being resistant to tampering or alteration.
Statement 2 is correct: Blockchain is accessible across a network of computers, copies of the entire database are stored and distributed across multiple nodes (computers) on the network.
Statement 3 is not correct: It is Hybrid Blockchain not Consortium blockchain which is described as a blend of public and private blockchains allowing selective data access. Consortium blockchain is semi-decentralized and governed jointly by multiple organizations for shared data management and validation.
Statement 4 is correct: Once a transaction is recorded on the blockchain, it cannot be modified or deleted. Mathematical/cryptographic algorithms make the blockchain an immutable and tamper-proof ledger that provides a high degree of security and trust.
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The Notification for the Civil Services Examination, 2021 was released by the Commission on March 04, 2021. The notification contains all the details related to the examination dates, number of vacancies, eligibility criteria, syllabus, application process, fee, exam centers etc. The exam is being conducted to fill in 712 vacancies as listed in the notification with 22 vacancies reserved for Persons with Benchmark Disability. The Preliminary examination will be held on October 10 2021. Candidates can visit the Commission’s website to fill the application form. Detailed instructions for filling up online applications have been provided on the website. The application window was closed on March 24 2021. The admit cards for the Preliminary Examination were made available from September 16 2021. The admit cards can be downloaded from the Commission’s website on the above mentioned link.