The transitive closure of { < 1, 2 >, < 1, 3 >, < 2, 4 > } is, a. {1, 2 >, < 1, 3 > < 2, 4 >}
b. {< 1, 2 >, < 1, 3 >, < 2, 4 >, < 1, 4 >}
c. { < 1, 2 >, < 1, 3 >, < 1, 4 >, < 3, 4 > }.