|q⟩ Bad Qubits

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Multiple choice
After this circuit, what is P(|111⟩) for the whole 3-qubit register measured together (qubit 0 leftmost)?
⚛ The apparatus
const c = circuit(3);
c.h(0);       // (|0>+|1>)/sqrt2 on qubit 0
c.cx(0, 1);   // copy onto qubit 1
c.cx(0, 2);   // copy onto qubit 2  ->  (|000>+|111>)/sqrt2
return c;

Commit your prediction for P(|111⟩) — then run it.