If a hacker wanted to change a transaction, what percentage of block copies would he/she need to change?
A. 20%
B. 51%
C. 10%
D. None of the above
Answer:A
If a hacker wanted to change a transaction, what percentage of block copies would he/she need to change?
A. 20% B. 51% C. 10% D. None of the above
Explanation: A hacker would need to change 51% of block copies. This is referred to as a 51% attack. There are also cases where an attack could happen when a miner controls 30% of nodes in the blockchain.