Frankie argues that the fraction 20−−√ is a rational number because the square root of 20 is 10. Frankie believes that because 10 is a whole number, it is rational. Alejandro disagrees. He believes that 20−−√ is a rational number because the square root falls between 4 and 5, and the decimal terminates.

Which statement BEST describes who is correct?
A
Frankie is correct because the 20−−√ is 10 which is a rational number.

B
Alejandro is correct because the 20−−√ falls between 4 and 5 and the decimal terminates.

C
Both students are correct because 20−−√ is a rational number.

D
Neither student is correct because 20−−√ is an irrational number.