In a Custom Module You Are Adding a New Field

In a custom module you are adding a new field to the store configuration. The field will set the value for the configuration path mycompany/mymodule/myoption. How do you supply the default value for that configuration option?

A) In the config/default/mycompany/mymodule/myoption node in the etc/config.xml file
B) In the system/mycompany/group/mymodule/field/myoption node in the etc/system.xml file
C) In the menu/default/section/group/field node in the file etc/adminhtml/menu.xml
D) In the system/section/group/field/value node in the etc/adminhtml/system.xml file