|q⟩ Bad Qubits

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Multiple choice
Run this circuit, then measure all 3 qubits at once. What is the probability of the joint outcome |111⟩ (qubit 0 leftmost)?
⚛ The apparatus
const c = circuit(3);
// Prepare the data qubit in |+> = (|0> + |1>)/sqrt(2).
c.h(0);
// Spread it across the code block with two CNOTs.
c.cx(0, 1);
c.cx(0, 2);
return c;

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