The number 189 is equal to the sum of the cubes of two integers. What is the product of those integers?	Choose the most appropriate option:  A) 8  B) 15  C) 20  D) 27  E) 39

Rationale: "4 ^ 3 + 5 ^ 3 = 189 the number is 4 * 5 = 20 c"
Answer: C