What does the Pauli-X gate do?

Question: What is the effect of applying a Pauli-X gate to a qubit in state |0⟩? A) It changes |0⟩ into |1⟩ B) It creates an equal superposition C) It measures the qubit D) It adds a global phase only Correct: A Explanation: The Pauli-X gate is the quantum equivalent of a classical NOT gate. It flips the computational basis state, transforming |0⟩ into |1⟩ and |1⟩ into |0⟩. Topic: quantum computing / gates / Pauli-X