Why Do We Do Overall Tests When Comparing Multiple Proportions

Multiple Choice

Why do we do overall tests when comparing multiple proportions and not just do the follow-up confidence intervals?

A) Doing an overall test will more likely lead to significant results than just doing the follow-up confidence intervals.
B) Doing an overall test allows us to see exactly which group is significantly different from which other groups.
C) Doing an overall test allows us to quickly get our results, while the follow-up confidence intervals are very time-consuming.
D) Doing an overall test allows us to keep the probability of a type I error at 5% or whatever significance level we would like.