In a cohort study investigating risk of breast cancer among women by age at first birth, a women was classified as "exposed" if she first gave birth at age 30 years or older. In a sample of 4540 women who gave birth to their first child before age 30, 65 developed breast cancer. Of the 1628 women who gave birth to their first child at age 30 or older, 31 were diagnosed with breast cancer. Based on the information provided, what is the excess risk of breast cancer in those classified as exposed? Give your answer in per 100,000. Formula Sheet: Formula Sheet.pdf O A. 752 per 100,000 O B. 134 per 100,000 O C. 470 per 100,000 O D. 1.33 per 100,000