If mn represents a positive two digit number, where m and n are single digit integers, which of the following cannot be true?	Choose the most appropriate option.
A) m+n =9 B) (m)(n)=9 C) m-n = 9 D) n-m= 9 E) m/n = 9
(A) mn = 45 or 63 or 27   (B) mn = 33 or 19   (C) 90   (D) impossible   (E) mn = 91   (D) is impossible because 09 is not a valid two digit number --- if there's a zero in the ten's place, that's just 9, a single digit number. Therefore, no valid two digit number would satisfy (D).   ans n-m= 9
<result>D</result>
If mn represents a positive two digit number, where m and n are single digit integers, which of the following cannot be true?