A 58-year-old woman who had a total abdominal hysterectomy at the age of 45 is diagnosed with atrophic vaginitis. Which of the following is the most appropriate treatment?
a. Conjugated estrogen 0.625 mg/day oral
b. Estradiol 7.5 mcg/24 hr vaginal ring
c. Medroxyprogesterone 10 mg/day oral
d. Conjugated estrogen 0.3 mg + medroxyprogesterone 1.5 mg/day oral