1.2.2 has answered your question. It is a cat C airplane normally at normal landing flap Vref and max certified landing weight, but note that it has to be capable of circling at the specified speed as well as landing at the stated Vref. If the Vref happened to be at a Cat B value at some very light weight on a particular occasion, it still could not be legally operated to Cat B. However, if it was in an abnormal configuration carrying less flap so that either the circling or Vref speed went above the Cat C limit, yes, you most definitely do need to apply Cat D minima or risk the ire of the subsequent court of inquiry if it goes wrong and they start looking for a scapegoat. It's not about practicality as a few more knots probably would not put you into the trees unless you were really wide on the circling - it's about a fine point of law.