In a manufacturing study two machine settings yield average defect rates 14 and 11 (units: percent). Each setting used n = 16 samples, and MSE from ANOVA is 4.0. If the q critical value is 4.30, compute q for these two settings and the Tukey decision.

• A. q = 6.00; reject H0 — the machine settings produce different defect rates.
• B. q = 1.50; fail to reject H0 because this q is below the critical threshold for Tukey post hoc comparison.
• C. q = 12.00; extremely significant difference, so strongly reject H0 without needing further verification.
• D. q = 0.50; indeterminate result that would require bootstrapping to resolve confidently.

Answer: (A)