With the sequence of the gene-coding regions of the human genome in hand and the development of newer sequencing methods,scientists ____.

A) now know that the types of mutations present in all cancers are very similar
B) can now sequence and analyze the protein-coding genes in cancer cells
C) are still unable to systematically identify all the mutations present in a cancer cell
D) found that the number of mutational events that occur during the transition from normal to malignant cells is much smaller than previously thought
E) found that most tumors had at least 100 mutations in common with any other tumor, emphasizing the common origin of cancer