# Assessment 4 #### What is the purpose of the Proof-of-work mechanism in the Bitcoin blockchain? (Choose ALL that apply) * [x] To determine who gets to update transactions * [x] To validate the existence and validity of transactions * [ ] To create new blocks without any computational effort * [ ] To eliminate the need for consensus among nodes **Notes to Learners** Proof of Work is the mechanism that determines who gets to update transactions on the Bitcoin blockchain. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://hub.bsvblockchain.org/higher-learning/bsv-academy/bitcoin-whitepaper-series/bitcoin-whitepaper-abstract/assessment-4.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.