A. A distributed ledger on a peer-to-peer network
B. A type of Cryptocurrency
C. An exchange
D. A centralized ledger

Solution

A. A distributed ledger on a peer-to-peer network

Explanation

Blockchain is a decentralized and distributed digital ledger technology that records transactions across multiple computers or nodes in a transparent and immutable manner. It is often associated with cryptocurrencies like Bitcoin, but its applications go beyond digital currencies.