I can’t image such a question asking for two terms to be explained for 6 marks – if you have such a question, presumably you also have an answer.
If the question was to explain the need for the exercise of professional scepticism and professional judgement – that would most likely be 1 mark each for stating what each term means – and 4 marks for explaining the need. For example, to recognise circumstances that may exist to cause the financial statements to be misstated or audit evidence that contradicts other audit evidence obtained.