Cyber Security and Digital Currency: Question 10

Worked solution

Step 1: Identify what each candidate feature/threat describes

• Encryption is the scrambling of data so that it cannot be understood without the correct key; it is about protecting the content of data, not about who approves a transaction.
• Two-step verification is a login/authentication method requiring two separate pieces of evidence of identity, such as a password and a code.
• Data interception is a threat where data is secretly captured while travelling across a network.
• Decentralisation means that transactions are checked and approved by the network of computers running the currency’s software collectively, rather than by one single central authority such as a bank.

Step 2: Match the scenario to the correct feature

The scenario describes each payment being checked and added to the shared record by the network of computers running the currency’s software, explicitly rather than by any single central bank or company approving it. This absence of one central controlling authority, replaced by the network itself validating transactions, is exactly what decentralisation means.

Step 3: Rule out the distractors

• Not encryption: the scenario is about who validates the transaction, not about scrambling the transaction’s data.
• Not two-step verification: no login process or identity check is described at all.
• Not data interception: this is a threat describing unauthorised access to data in transit; the scenario describes the normal, legitimate way transactions in this system are approved.

Final answer

The feature described is decentralisation, option B.