A 71-year-old male has been recently diagnosed with a stage III tumor of colorectal cancer and is ...

A 71-year-old male has been recently diagnosed with a stage III tumor of colorectal cancer and is attempting to increase his knowledge base of his diagnosis.
 
  Which of the following statements about colorectal cancer demonstrates a sound understanding of the disease?
  A)
  If accurate screening test for this type of cancer existed, it could likely have been caught earlier.
  B)
  The NSAIDs and aspirin that I've been taking for many years probably contributing to me getting cancer.
  C)
  While diet is thought to play a role in the development of colorectal cancer, the ultimate causes are largely unknown.
  D)
  A large majority of patients who have my type of colon cancer survive to live many more years.