In What Form(s) Will a Carboxylic Acid, RCOOH, Be Present

In what form(s) will a carboxylic acid, RCOOH, be present if the pH of an aqueous solution is adjusted to be the same as the pKa of the acid?

A) primarily as RCOOH (aq)
B) primarily as RCOO− (aq)
C) equal amounts of a and b
D) neither a nor b