Basics in Blockchain : Practice MCQ Questions & Answers with Explanations

Blockchain ensures the secure and efficient management of electronic health records (EHRs), providing patients and healthcare providers with better access and data integrity.

Blockchain enhances supply chain management by improving transparency and traceability of goods. It provides a tamper-proof record of the movement of goods, reducing fraud and inefficiencies.

Blockchain security relies on encryption techniques and consensus mechanisms like Proof of Work (PoW) or Proof of Stake (PoS), which ensure data integrity and prevent unauthorized alterations.

Hashing is used to create a unique, fixed-length representation of data. Any change in the data results in a different hash, ensuring data immutability and integrity.

Private keys are critical for accessing and authorizing blockchain transactions, providing users with control over their assets and ensuring secure interactions.

A Sybil attack occurs when an attacker creates multiple fake nodes to disrupt the network's operations, potentially influencing consensus mechanisms and reducing trust.

Public blockchains can be exposed to Distributed Denial-of-Service (DDoS) attacks and scalability issues due to their open nature, which requires robust security mechanisms to mitigate risks.

Blockchain scalability faces the challenge of maintaining a balance between transaction speed, throughput, and decentralization. Increasing one often impacts the others, commonly referred to as the "scalability trilemma."

Sharding splits the blockchain network into smaller partitions, or shards, enabling parallel processing of transactions and increasing scalability.

Ethereum 2.0 uses Proof of Stake to reduce energy consumption and sharding to increase transaction throughput, addressing scalability issues.

Rollups are Layer 2 solutions that aggregate multiple transactions into a single batch for submission to the main blockchain, reducing load and increasing scalability.

Block time refers to the duration it takes to generate and append a new block to the blockchain, impacting transaction confirmation speeds.

Blockchain governance refers to the decentralized process where stakeholders, such as miners, validators, and developers, collectively make decisions about network changes and upgrades.

Developers contribute to blockchain governance by proposing upgrades, implementing patches, and maintaining the core protocol, ensuring smooth network functionality.

A hard fork occurs when a blockchain splits into two separate networks, requiring updates and changes that are incompatible with previous versions.

Validators validate transactions and add them to the blockchain, playing a crucial role in maintaining consensus and ensuring the network's integrity.

Blockchain enables faster, more cost-effective financial transactions with built-in transparency and audit trails, which reduce the need for intermediaries.

Immutable blockchain records ensure that audits are transparent, tamper-proof, and verifiable in real time, making compliance easier.

Blockchain stores business data in an encrypted, unalterable manner, ensuring that all analytics are based on accurate and trustworthy records.

Blockchain enhances loyalty programs by securely and transparently tracking customer interactions and reward distributions without fraud risks.