Answer:
Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile.
Explanation:
From given scatter plot, we see that upper quartile of Mrs. Cai's class = 4
lower quartile of Mr. Roland’s class = 4
Both are equal so that means.
That means Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile.
Hence last choice is correct.