Blake simplified the expression (X^12 / X^-3) to 1/ X^20. What was Blake’s mistake?
A) He added 5 to the exponent in the numerator instead of multiplying.
B) He subtracted the exponents in the parentheses instead of dividing.
C) He multiplied only the exponent in the numerator of the fraction by 5.
D) He divided the exponents in the parentheses instead of subtracting.