A BIND server should be upgraded to use TSIG. Which configuration parameters should be added

A BIND server should be upgraded to use TSIG. Which configuration parameters should be added, if the server should use the algorithm hmac-md5 and the key skrKc4DoTzi/tAkllPi7JZA== ?

A.
TSIG server.example.com.
algorithm hmac-md5;
secret "skrKc4DoTzi/tAkllPi7JZA==";
};

B.
key server.example.com. {
algorithm hmac-md5;
secret skrKc4DoTzi/tAkllPi7JZA==;
};

C.
key server.example.com. {
algorithm hmac-md5;
secret "skrKc4DoTzi/tAkllPi7JZA==";
};

D.
key server.example.com. {
algorithm=hmac-md5;
secret="skrKc4DoTzi/tAkllPi7JZA==";
};

E.
key server.example.com. {
algorithm hmac-md5
secret "skrKc4DoTzi/tAkI1Pi7JZA=="
};