21 point Which is $\frac{21}{72}$ in lowest terms? a. $\frac{7}{18}$ c. $\frac{21}{72}$ b. $\frac{14}{48}$ d. $\frac{7}{24}$

Step 1 ：The question is asking for the fraction \(\frac{21}{72}\) in its simplest form. To find this, we need to find the greatest common divisor (GCD) of 21 and 72 and then divide both the numerator and the denominator by this GCD.

Step 2 ：numerator = 21

Step 3 ：denominator = 72

Step 4 ：gcd = 3

Step 5 ：simplest_form = (7, 24)

Step 6 ：Final Answer: The fraction \(\frac{21}{72}\) in its simplest form is \(\boxed{\frac{7}{24}}\). Therefore, the correct answer is option d. \(\frac{7}{24}\).