Answer:
d. {red pen, blue pen, green pen, yellow pen, black pen}
Explanation:
Be
A = Colors of pens in the first box
B = Colors of pens in the second box
A = {red, blue, green}
B = {yellow, red, black}
D =? set that represents all the pens
In set theory, the union of two (or more) sets is an operation that results in another set, whose elements are the same as the initial sets, without repeating those that are the same.
Therefore, the set that represents all the pens is:
D = {red, blue, green, yellow, black}
Hope this helps!