To swap the states of two qubits.

To entangle two qubits.

To measure the state of a qubit.

To apply a Hadamard gate to a qubit.

$$[ \begin{pmatrix} 1 & 0 & 0 & 0 \ 0 & 0 & 1 & 0 \ 0 & 1 & 0 & 0 \ 0 & 0 & 0 & 1 \end{pmatrix} ]$$

$$[ \begin{pmatrix} 0 & 1 & 0 & 0 \ 1 & 0 & 0 & 0 \ 0 & 0 & 0 & 1 \ 0 & 0 & 1 & 0 \end{pmatrix} ]$$

$$[ \begin{pmatrix} 0 & 0 & 1 & 0 \ 0 & 1 & 0 & 0 \ 1 & 0 & 0 & 0 \ 0 & 0 & 0 & 1 \end{pmatrix} ]$$

$$[ \begin{pmatrix} 1 & 0 & 0 & 0 \ 0 & 1 & 0 & 0 \ 0 & 0 & 1 & 0 \ 0 & 0 & 0 & 1 \end{pmatrix} ]$$

A square with two lines crossing in the middle.

A circle with two lines crossing in the middle.

A triangle with two lines crossing in the middle.

A diamond with two lines crossing in the middle.

The SWAP gate itself.

The CNOT gate.

The Hadamard gate.

The Toffoli gate.

To create entanglement between qubits.

To implement quantum teleportation.

To perform quantum Fourier transforms.

All of the above.

1

2

3

4

O(1)

O(log n)

O(n)

O(n^2)

Yes

No

To detect errors.

To correct errors.

Both of the above.

None of the above.

It creates entanglement between the two qubits.

It destroys entanglement between the two qubits.

It has no effect on the entanglement between the two qubits.

It depends on the initial state of the two qubits.

To simulate the dynamics of a quantum system.

To simulate the properties of a quantum material.

Both of the above.

None of the above.

It swaps the state of the qubit with itself.

It flips the state of the qubit.

It has no effect on the state of the qubit.

It depends on the initial state of the qubit.

To generate secret keys.

To distribute secret keys.

Both of the above.

None of the above.

It increases the fidelity of the quantum state.

It decreases the fidelity of the quantum state.

It has no effect on the fidelity of the quantum state.

It depends on the initial state of the quantum state.

To measure the phase of a quantum state.

To measure the amplitude of a quantum state.

Both of the above.

None of the above.