Consider the following statements about Bitcoin and similar 'cryptocurrencies': I. Bitcoin is a decentralised electronic payment system. II. Only a finite number of bitcoins can ever be created by miners. III. Bitcoins are indivisible units of currency. IV. Every single bitcoin transaction is recorded in a public ledger called the blockchain. Which of the above statements are correct?

Introduction / Context:
Bitcoin is the first and most well known cryptocurrency and is frequently mentioned in questions on Indian economy and general awareness. To answer such questions accurately, it is important to understand the basic design features of Bitcoin, including decentralisation, supply limits, divisibility, and the concept of blockchain. This question presents four statements about Bitcoin and asks you to identify which of them are correct, testing both conceptual clarity and attention to detail.

Given Data / Assumptions:

• Statement I: Bitcoin is a decentralised electronic payment system.
• Statement II: Only a finite number of bitcoins can ever be created by miners.
• Statement III: Bitcoins are indivisible units of currency.
• Statement IV: Every bitcoin transaction is recorded in a ledger called the blockchain.
• We assume standard technical descriptions of Bitcoin as implemented in practice.

Concept / Approach:
Bitcoin was designed as a decentralised digital currency that does not depend on a central authority such as a government or central bank. Transactions are verified by a network of nodes and recorded in a distributed ledger known as the blockchain. The Bitcoin protocol has a built in limit on the total number of bitcoins that can ever be mined, often cited as 21 million. However, bitcoins are highly divisible; each bitcoin can be divided into many smaller units (the smallest commonly referred to as a satoshi), so the claim that bitcoins are indivisible is incorrect. The correct approach is to evaluate each statement in light of these basic facts.

Step-by-Step Solution:
Step 1: Evaluate Statement I. Bitcoin does not rely on a central issuing authority; it operates on a peer to peer network, so it is correctly described as a decentralised electronic payment system.Step 2: Evaluate Statement II. The Bitcoin protocol sets a maximum supply cap, meaning that only a finite number of bitcoins can ever be created by mining. This statement is correct.Step 3: Evaluate Statement III. Bitcoins are not indivisible; one bitcoin can be split into many smaller units, allowing very small value transactions. Therefore, this statement is incorrect.Step 4: Evaluate Statement IV. Bitcoin uses a distributed ledger technology known as the blockchain, where every confirmed transaction is recorded in blocks that are cryptographically linked. This description is correct.Step 5: Combine the correct statements. Statements I, II and IV are correct, while III is incorrect.Step 6: Among the given options, the combination (i), (ii) and (iv) corresponds to this set of correct statements.

Verification / Alternative check:
To verify, consider how Bitcoin functions in practice. Users send and receive bitcoins through digital wallets without a central clearing house, which illustrates decentralisation. Mining rewards and the halving schedule are defined in the protocol in such a way that total supply approaches a fixed upper limit, confirming statement II. Wallet applications routinely allow users to specify amounts far smaller than one bitcoin, for example 0.001 or 0.00000001 bitcoin, showing that bitcoins are divisible and invalidating statement III. Finally, blockchain explorers allow anyone to view the history of transactions recorded in the ledger, which supports statement IV. This cross check confirms that only I, II and IV are correct.

Why Other Options Are Wrong:
(i), (ii) and (iii): This option wrongly includes statement III, which claims that bitcoins are indivisible units, contradicting their actual divisibility.

(i), (iii) and (iv): This combination again includes the incorrect statement about indivisibility and omits the correct statement II about finite supply.

(i), (ii), (iii) and (iv): This suggests all statements are correct, but statement III is clearly false.

(ii), (iii) and (iv): This option excludes the correct statement I on decentralisation and includes the incorrect statement III.

Common Pitfalls:
Many learners confuse the idea of a finite total supply with indivisibility and assume that if the number of bitcoins is capped, each unit must be indivisible. In reality, cryptocurrencies can have both a fixed maximum number of units and high divisibility at the same time. It is also easy to overlook the decentralised nature of Bitcoin and think of it as being controlled by some central company or authority. Keeping the core features distinct decentralisation, fixed supply cap, divisibility, and blockchain recording helps in accurately evaluating statements in exam questions.

Final Answer:
The correct statements are I, II and IV, so the right option is (i), (ii) and (iv).