A sample test for you with UNPIVOT, ran in sqlfiddle.com
CREATE TABLE geek
(id int, [choice1] int, [choice2] int)
;
INSERT INTO geek
([id], [choice1], [choice2])
VALUES
(1, 10, 20),
(2, 30, 0),
(3, 0, 40)
;
SELECT
id
, choice
FROM geek
UNPIVOT (
choice
FOR value in (choice1, choice2)
) unpiv
WHERE choice > 0
;
id choice
1 10
1 20
2 30
3 40
sqlfiddle link[
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