* 19. Alejandro wants to use the least common denominator to write equivalent fractions for 3/7 and 4/5. He rewrites the fractions as 15/35 and 20/35. How should he change his answer?
A. The numerators are correct, but the denominators should be 7.
B. 20/35 is correct, but 15/35 should be 21/25. C. 15/35 is correct, but 20/35 should be 28/35. D. the denominators are correct, but both numerators should be 12.. PLEASE ANSWER!