You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is True about otosclerosis -a) 50% have family historyb) Males are affected twice than femalesc) More common in Negro's and African'sd) Deafness occurs in 20-30 yrs but less in before 10 yrs and after 40 yrse) Pregnancy has bearing on it and explain in detail?
None