Which configuration parameters should be added, if the server should use the algorithm hmac-md5 and the key skrKc4DoTzi/tAkllPi7JZA== ?

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=="
};