Bad Qubits — Learn Quantum by Doing

Multiple choice

The lesson explains that the naive 'store a qubit three times and majority vote' strategy fails for quantum error correction. What is the fundamental reason?

The no-cloning theorem forbids copying an unknown quantum state, so a qubit cannot be literally triplicated
Majority voting requires a classical computer, which quantum hardware lacks
Three qubits are not enough; you would need at least nine to vote
Qubits cannot be measured at all, so a vote is impossible to read out