Are Dual US citizens Foreign Contacts?

Seen this question come up a lot through here but have yet to find a definitive answer. Filling out my SF86 and not sure as to what to put. On the SF it states they are defined as non citizens. I have family who are US citizens and also have citizenship for out birth country(Central America) therefore Dual Citizens. They also live in the states. Whats your opinion on this? Thank you in advance !