A 51% attack refers to a situation where a single miner or group controls more than 50% of the

blockchain network’s computational (hashing) power. This majority control allows them to

manipulate the blockchain ledger by double-spending or blocking transactions.

This term is widely recognized in blockchain security contexts and is referenced in typology papers on

crypto financial crime risks, including those issued by UAE authorities and FATF.

Supporting extracts:

DFSA AML thematic reviews mention the risk of manipulation and double spending in blockchains

susceptible to 51% attacks.

Typology reports on cryptoasset risks highlight computational power concentration as a core

vulnerability.

“51% refers to the percentage of total mining power or computational power in the network” is the

standard definition across crypto AML/CFT frameworks【31.92._TFS_Typology_Paper_Eng__4.pdf;

AMLCFT_Guidance_for_FIs.pdf】.

Thus, C is correct.