A bag contains yellow-, blue-, green-, and red-colored chips. The table below shows the results of selecting one chip from the bag, recording the color, and then replacing the chip. What is the experimental probability of selecting a chip that is either green or red?
A. 1/4 = 25%
B. 3/4 = 75%
C. 1/2 = 50%
D. 1/3 ≈ 33%