Question

Look at the sets below.
{7, 8, 9, 10} {9, 10, 11, 12}
Which of the following shows the union of the sets?
A. {9, 10}B. {7, 8, 9, 10}C. {9, 10, 11, 12}D. {7, 8, 9, 10, 11, 12}