What does a stabilizer tableau efficiently track?

Question: In Gottesman–Knill style simulation, why can Clifford circuits be classically simulated efficiently? A) Clifford circuits never create entanglement B) Clifford gates always keep the full quantum state as a product state C) Clifford gates map Pauli operators to Pauli operators, allowing stabilizers to be updated compactly D) Clifford gates diagonalize every Hamiltonian in polynomial time Correct: C Explanation: Clifford circuits can create entanglement, but they preserve the stabilizer structure. Since Clifford gates conjugate Pauli operators into Pauli operators, the stabilizer description can be updated efficiently without storing 2^n amplitudes. Topic: advanced quantum computing / stabilizer formalism / Gottesman-Knill