There is a question in an aqa biol 5 paper (june 2010 question 6 (c) (ii)) that asks, why a patient in a trial might develop cancer. The answer states that it is the inactivation of tumour suppressor genes that cause it. (it doesn't allow oncogenes as an answer.
But how do I know whether it's the inactivation of tumour suppressor genes or the activation of oncogenes causing the cancer?
I cannot find any clue in the question.
Please help..