What can happen if an exchange knows your identity and you reuse the same Bitcoin address?
Correct answer
Answer D: Several transactions can be linked to you more easily.
Quick explanation
Under KYC, or 'Know Your Customer', the provider knows your identity. Reusing the same address makes it even easier to link multiple payments.
Detailed explanation
KYC means a service collects and verifies customer identity data. An exchange can thereby know who uses an account and which Bitcoin address they withdrew to. This information does not automatically appear publicly as a real name on the blockchain, but may exist at the service, through authorities' access, data leaks or onward sharing.
Address reuse is a separate problem. If the same receiving address is published or used repeatedly, payments, total amounts and activity over time become easier to group. Once linked to a person or organization, the association may cover every visible transaction of that address.
The effects can reinforce each other: KYC provides an identity link, and reuse enlarges visible connections. A new receiving address per payment reduces this simple linkage but does not eliminate all analysis methods. Shared inputs, change, counterparties and network data can still offer clues. Privacy is therefore a chain of decisions, not one wallet setting.
Example or everyday application
An exchange records a withdrawal to address X. If X is later reused for many public receipts, these payments become easier to associate with the same known recipient.
Common misconception
Many believe a new address solves every privacy problem or that KYC writes names directly into the blockchain. The explanation separates internal records from public analysis.
Sources used
Protect your privacy
Check original sourceBitcoin Core 31.0 - createwallet, avoid_reuse
This source is mainly intended for developers. The relevant information may therefore be harder to find.
Check original source