Free practice exam
Crypto & Blockchain Investigator (CBI) practice questions
Practise blockchain tracing: Bitcoin-style and Ethereum-style chains, bridges and mixers, privacy tools, and how freezes and reports work.
These 15 questions are separate from the real CBI final exam, so you can see every answer here. Pick an option to check yourself, and use the chapter link to revise.
Score: 0 / 0 answered · 15 questions
1. Why is a public blockchain called 'pseudonymous' rather than anonymous?
Answer: B. Transactions are public and tied to addresses, which can sometimes be linked to real people
Addresses are not names, but the public record can be linked to identities through exchanges and other data.
Study this in chapter 12. Once a Bitcoin transaction is confirmed, can the sender reverse it?
Answer: B. No — there is no built-in chargeback
Confirmed transactions are final, which is why speed in contacting exchanges matters.
Study this in chapter 13. In Bitcoin's UTXO model, what is 'change'?
Answer: B. The leftover amount returned to an address controlled by the sender
Inputs are spent in full; the remainder goes back to a change address, which tracers try to identify.
Study this in chapter 24. The 'common-input-ownership' heuristic assumes what?
Answer: B. Addresses used together as inputs in one transaction are likely controlled by the same party
It is a widely used clustering assumption, but CoinJoin and similar techniques can break it.
Study this in chapter 25. On Ethereum, what is the difference between an externally owned account and a contract account?
Answer: B. An externally owned account is controlled by a private key; a contract account runs code
Knowing which you are looking at changes how you read the flow of funds.
Study this in chapter 36. A victim 'approved' a token for a malicious site. What risk remains even after the site is closed?
Answer: B. The approval can let the attacker's contract move those tokens until it is revoked
Token approvals persist; revoking them on-chain stops further draining.
Study this in chapter 37. Where do investigators read Ethereum transaction history publicly?
Answer: A. A block explorer such as Etherscan
Block explorers display transactions, token transfers and contract interactions.
Study this in chapter 38. Why do criminals use cross-chain bridges?
Answer: B. To move value between blockchains and make tracing harder
Bridges add hops across chains; tracers must follow the matching deposit and withdrawal.
Study this in chapter 49. What does a mixer or tumbler try to do?
Answer: B. Break the visible link between deposits and withdrawals by pooling funds
Mixing obscures the trail. Some mixers have been sanctioned by authorities.
Study this in chapter 410. Which coin is designed with privacy features that hide amounts and parties by default?
Answer: B. Monero
Monero uses ring signatures, stealth addresses and confidential amounts by default.
Study this in chapter 511. What is the Lightning Network?
Answer: B. A second-layer payment network for Bitcoin where many payments happen off-chain
Off-chain channel payments do not appear individually on the main chain, which limits tracing.
Study this in chapter 512. Stolen USDT on Ethereum sits in a scammer's address. Who may be able to freeze it?
Answer: B. The stablecoin issuer (Tether) can freeze addresses, typically on law-enforcement request
Centralised stablecoin issuers can blacklist addresses, which is why fast reporting matters.
Study this in chapter 613. What usually links a wallet to a real identity?
Answer: B. A regulated exchange's know-your-customer records, obtained through legal process
Exchanges hold identity data; police access it through lawful requests.
Study this in chapter 614. What should a tracing report include?
Answer: B. Transaction hashes, addresses, amounts, timestamps and the reasoning for each hop
Each step must be verifiable by someone else reading the report.
Study this in chapter 615. A victim sent Bitcoin to an exchange deposit address. What is the most useful next step?
Answer: B. Report to police and contact the exchange quickly with the transaction hash
Exchanges can sometimes hold funds if alerted early with precise transaction details.
Study this in chapter 2
Ready for the real CBI final exam?
The final uses different questions drawn from the same chapters. Track your attempts and study material in your course portal.
Authoritative sources
Independent primary sources used to check and corroborate the guidance on this page.
NIST National Initiative for Cybersecurity Education (NICE)US national framework for cybersecurity work roles and competencies.
Financial Action Task Force (FATF)Global AML/CFT standards referenced by financial-crime curricula.
FBI Internet Crime Complaint Center — Annual ReportsPrimary loss and typology data used in fraud-investigation training.
US Federal Trade Commission — Consumer Sentinel Data BookOfficial complaint statistics for teaching fraud trend analysis.