THURSDAY: 4 August 2022. Morning paper. Time Allowed: 2 hours.
This paper has two sections. SECTION I has twenty (20) multiple choice questions. SECTION II has three (3) practical questions of sixty (60) marks. All questions are compulsory. Marks allocated to each question are shown at the end of the question.
SECTION I
1. The following are some application platforms of Blockchain. Which one is NOT? (2 marks)
A. Ethereum
B. NEO
C. Stellar
D. Bitcoin
2. Which one of these is designed to find the rates between two digital assets, making it trade crypto? (2 marks)
A. Stellar’s SDEX Exchange
B. NEO’S NEX Exchange
C. EtherDelta
D. Ether
3. Following are some important stakeholders of Blockchain ecosystem. Which one is NOT? (2 marks)
A. Users
B. Developers
C. Miners
D. Exchangers
4. Encryption uses secret key whereas tokenization uses _______. (2 marks)
A. Public key
B. Token
C. Obfuscation
D. Algorithm
5. Below is a list of asset tokenization platforms. Which ONE is NOT? (2 marks)
A. Harbor
B. Neufund
C. Bitbond
D. Decurrency
6. ___________ defines the earliest time that a transaction can be added to the Blockchain. (2 marks)
A. Locktime
B. Commence
C. Input time
D. Activity start
7. Write the acronym UTXO in full. (2 marks)
A. Unified transaction output
B. Universal transaction output
C. Unspent transaction output
D. Unspent transaction xolair
8. Where is Merkle Root stored in Bitcoin network? (2 marks)
A. In the last block
B. In the new block
C. In the next block
D. In the block header
9. How can blocks in the Blockchain be identified? (2 marks)
A. By block height and block header hash
B. By block name and size
C. By their position in the Blockchain
D. By the block name and function
10. What is coinbase transaction as used in Bitcoin? (2 marks)
A. Transaction in form of coins
B. First transaction in a block
C. A reserve of coins in Bitcoin
D. The last transaction in block
11. What is proof of stake transaction as used Blockchain technology? (2 marks)
A. Certificate required to use Blockchain
B. A password needed to access an exchange
C. Algorithm used to confirm the transaction and creates a new block to the chain
D. A transaction and block verification protocol
12. The list below is of some forms of incentives to the miners in Blockchain technology. Which ONE is NOT? (2 marks)
A. Coins reward
B. Block Rewards
C. Incentive Pools
D. Cryptocurrency reward
13. Which of the following is a type of consensus algorithm in Blockchain? (2 marks)
A. Proof-of- Worth
B. Proof-of-Stakeholder
C. Proof-of-Authority
A. Proof-of-Delayed Time
14. What are the types of records that are present in the Blockchain database? (2 marks)
A. Fields and records
B. Transactional and block Records
C. Tables and block Records
D. Characters and Fields
15. What are non-fungible tokens as used in Blockchain technology? (2 marks)
A. Unique digital assets that verify ownership of a specific item
B. Unique physical assets that verify ownership of an item
C. Non digital cash emanating from a digital transaction
D. Cryptocurrencies that can be traded for the same item
16. Select ONE statement that does NOT represent a challenge of Bitcoin. (2 marks)
A. Not scalable
B. Not popular
C. Does not have any inherent value
D. Not energy efficient
17. While buying crypto, one should keep in mind all the following EXCEPT? (2 marks)
A. Utility
B. Total number of crypto supply
C. Market capitalization
D. Ease of use of digital platform
18. If you are the Chief Technologist Officer of an IT organization, which of the following use cases would you focus on for an immediate production? (2 marks)
A. Authenticated provenance
B. Decentralized web
C. Non-fungible tokens
D. Blockchain managed services
19. Which of the following cryptocurrencies does NOT work on the proof of work consensus model? (2 marks)
A. Allcoin
B. Bitcoin
C. Monero
D. Dogecoin
20. Select among the following a backward compatible temporary fork. (2 marks)
A. Universal fork
B. Hard and soft fork
C. Nonce fork
D. Intermediate fork
SECTION II
21. The figure below shows a typical flow of how a transaction gets into the Blockchain. Explain what is happening at each of the stages in order to complete the transaction. (20 marks)
22. A transaction is a data structure that encodes a transfer of value from a source of funds, called an input, to a destination, called an output. Complete the table below of transaction structure by typing the correct size, field or description labelled (a) to (g). (20 marks)
23. Consider a block having 4 transactions: T1, T2, T3, T4. These four transactions have to be stored in the Merkle tree.
Explain steps followed to compute the hash of each transaction and draw the resulting Merkle tree. (20 marks)
