Going with C. Without explicit language to the president, they will need to interpret this to mean the president included, which may be up to anyone’s interpretation.

I feel it should, however it could be argued it doesn’t.

who, having previously taken an oath, as a member of Congress, or as an officer of the United States, or as a member of any State legislature, or as an executive or judicial officer of any State, to support the Constitution of the United States, shall have engaged in insurrection or rebellion against the same, or given aid or comfort to the enemies thereof