Meaning of quantum entanglement

Question: What does quantum entanglement mean? A) Two qubits are stored in the same memory address B) Two qubits are correlated so their joint state cannot be described independently C) One qubit has both positive and negative charge D) A qubit is copied perfectly Correct: B Explanation: Entanglement is a quantum correlation between two or more quantum systems. In an entangled state, the complete system must be described as a whole, rather than as separate independent qubit states. Topic: quantum computing / entanglement