<prompt> First secondary ossification center appears inLower end of femurUpper end of humerusLower end of fibulaUpper end of tibia  <response>: Ans. is a i.e., Lower end of femur Site given in question Secondary ossification center appears at Lower end of femur 9th month intrauterine life Upper end of tibia At bih Upper end humerus 12 -1 year of age Lower end of fibula 1 year of age 