أخي الكريم الجواب الصحيح هو : usually. بالرجوع إلى المحتوى تجد..
It is obvious that not all texts are the same type. We may distinguish between political texts, legal texts and medical texts; fairy tales, novels and short stories differ from newspaper reports, essays and scientific papers; food recipes, instructions booklets and advertisements may show similarities but they are not the same, expository texts differ from argumentative texts, etc. ( Trosborg, 1998)

may show similarities تنفي الإختيار ( don't )
but they are not the same تنفي الإختيار ( always )
إذاً usually هي الإجابة الصحيحة لأنها تجمع ما بين الإختياريين السابقين. عادة تكون وأخرى لا تكون.

To be or not to be. This is the question.