Answer:
B. 3/4
Explanation:
Find the GCD (or HCF) of the numerator and denominator
GCD of 15 and 20 is 5
Next, divide both the numerator and denominator by the GCD
15 ÷ 5 = 3
20 ÷ 5 = 4
Finally, put them back into a fraction

Therefore, 15/20 simplified to the lowest terms is 3/4.