A quantum computer does not merely try every answer at once. If it did, measurement would return a random result from a superposition, yielding no advantage.
The actual mechanism is distribution. A classical bit is local and independent; a quantum register of qubits is a single global state vector with amplitudes. A quantum gate acts on all of them simultaneously.
Superposition spreads a local state across the whole basis. Entanglement distributes correlations so that no individual qubit holds the complete picture. Unitary evolution then rearranges these amplitudes globally.
A useful quantum algorithm arranges this evolution so that wrong answers cancel through destructive interference, while the right answer reinforces. The distinguishing information is not stored in any single qubit; it lives in the global pattern of phases.
Therefore, quantum computing is fundamentally about distributing information across an exponentially large state space and evolving it collectively so that measurement extracts the correct answer.