Marine Corps

Why does the chief of chaplains for the marine corps who is navy wear a marine corps uniform?
The current chief of chaplain for the marine corps is a navy admiral, why then is she wearing a marine corps uniform, she’s wearing the green service dress uniform with the eagle globe and anchor and everything. I just want insight does anyone know why this is? and also can a marine become the chief of chaplains for the marine corps?
Naval personnel assigned to USMC units have the option of wearing USMC uniforms (except for dress blues – they wear USN dress uniforms instead) This would include Hospital Corpsmen, Religious Program specialists (chaplain assistants) , Medical officers, Medical Service Corps officers, Chaplains. The USMC has no chaplains from its ranks – all chaplains are commissioned officers of the Navy.
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