Based on the control plot, which conclusion is justified regarding the means of the response?

Refer to the exhibit.

Based on the control plot, which conclusion is justified regarding the means of the response?
A . All groups are significantly different from each other.
B . 2XL is significantly different from all other groups.
C . Only XL and 2XL are not significantly different from each other.
D . No groups are significantly different from each other.

Answer: C