Echo is a handsome 10 year old pure bred Belgian Malinois . Echo is a retired police dog so all of his commands are in German and he is SO obedient . When Randy ( Echo 's first owner ) came to bring Echo to us , he showed us some quick obedience training and he also worked with April .
According to the above context, choose the best option to answer the following question.
Question: Why did Echo retire ?
Options:
A. He got to be too old .
B. He was disobedient .
C. He was n't good at his job .
D. The police force did n't want him anymore .


A