[USER (data scientist)]: I will create a code to outline the main features of each target customer group in the credit_customers dataset. The output will be a summary of these main features for each group. In response to this, could you also address my following question: How long should the employment duration be for customers to be retained through loyalty programs and encouraged to continue using the services of the financial institution?  

A. shorter
B. longer
C. moderate
D. zero
E. None of above

[YOU (AI assistant)]: