Which of the lists of letters all have line symmetry? 1. (A, B, C, D)
2. (W, X, Y, Z)
3. (L, M, N, O)
4. (S, T, U, V)

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Explanation:

Check out the diagram below to see where the lines of symmetry are located.

For the letter A, we have a vertical line through the center that is the mirroring line. Reflecting one half over that line generates the other half.

For letter B, we have a horizontal line through the center. This applies to letters C and D as well.

This is why answer choice 1 is the final answer.

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For letter Z, we have neither a vertical nor a horizontal mirror line. This letter doesn't have any lines of symmetry (though it does have rotational symmetry). So we can rule out answer choice 2.

Letter N is pretty much the same idea as letter Z. There aren't any lines of symmetry but we do have rotational symmetry. So we can rule out answer choice 3.

Lastly, we can rule out answer choice 4 because letter S has the same properties as letters Z and N.