You've Been Targeting the Entire United States in Your Scuba

You've been targeting the entire United States in your scuba diving equipment ad campaign, but you know that much of the scuba equipment that is sold is to customers in Hawaii. What would be the most efficient way to optimize your campaign and measure the impact of an optimization?

A) You create a separate campaign targeting only Hawaii so you can easily see how your campaign performs in that state, and adjust your budget.
B) You add the keywords "Hawaii" to all of your ad groups, so that your ad will stop serving on searches that are not specific to Hawaii.
C) You adjust your ad scheduling so that your campaign is only showing during business hours for the time zone that Hawaii is in.
D) You delete all of the keywords that have not been performing well, and start over with a new set of keywords and campaigns that uses location targeting to show only to users in Hawaii.