Genetic engineering has been successfully used for producing

$\text{Correct answer: B}$ 

$\text{Option (A):}$ 

$?$ Genetic engineering is not used for producing bulls that are used for farm work because of their abilities. 

$\text{Option (B):}$ 

$?$ Transgenic mice can be created by using genetic engineering which contains the specific characters suitable to show the effect of the polio vaccine. 

$?$ A trial was performed on the transgenic mice before it was introduced for human trials. 

$?$ This is to ensure the safety of the polio vaccine in humans. 

$\text{Option (C):}$ 

$?$ Transgenic models for studying the new treatments related to cardiac disorders are yet to be produced completely. 

$?$ Mice models containing cardiac disorders are being produced to determine the efficacy of specific drugs that can be used to cure those diseases. Such a mouse model is yet to be developed. 

$\text{Option (D):}$ 

$?$ The transgenic cow Rosie is specialized to produce milk with human alpha-lactalbumin protein.

$?$ It is not responsible for producing high-fat milk which is used for producing ghee.

Hence, the correct answer is option (B).