Which of the following scenarios violates the Isolation property in the ACID properties of a transaction? 

The Isolation property ensures that the operations of a transaction are isolated from other transactions. In scenario A, when a transaction reads uncommitted data from another transaction (dirty reads), the Isolation property is violated. This leads to incorrect or inconsistent data being processed if the uncommitted transaction rolls back or is otherwise altered before completion. Ensuring isolation prevents such scenarios, as transactions should not be able to see the intermediate states of other transactions. Why Other Options are Incorrect: B) A transaction rolls back after detecting a deadlock: This preserves consistency and is not a violation of Isolation. C) Multiple transactions write data concurrently but respect unique constraints: This scenario adheres to isolation as each transaction operates in its own space without interference. D) A transaction is lost due to a server crash: This is related to the Durability property, not Isolation. E) A transaction reads stale data: This is a violation of Consistency or Atomicity, depending on the situation, but not necessarily Isolation.