Until one month ago, the Vice Chief of Naval Operations was Admiral William Moran, who was also appointed by Obama.
Does Trump ever replace any of Obama’s appointees?
Certainly not at the Department of Homeland Security.
DOJ and FBI run a close second for retained Obama appointees.
Oddly, DHS had the one Obama appointee who sometimes sounds somewhat sane... Jeh Johnson. Check out his border comments, it’ll shock you that they come from someone in the Obama camp.