A mutant gene (ras) is found in up to a third of all human cancers, including lung, colon, and pancreas, and may be responsible in part for the altered metabolism in tumor cells. The ras protein encoded by the ras gene is involved in signaling pathways that regulate cell growth and division. Because the ras protein must be converted to a lipid-anchored membrane protein to have cellular signaling activity, the enzyme farnesyltransferase (FT) has been selected as a potential chemotherapeutic target for inhibition. Indicate why FT might be a reasonable target.