If I remember rightly Greenwich Uni wanted AAB, for theirs. I would try a resit, or a retake and see if you can get higher. As said above it is statistic based, but in my maths class I have a psychology masters student who hasn't got her GCSE yet, so it may well be if you show your keen to retake they will let you on the course. She said the stats are pretty much done on computers now, so not as bad as it used to be.