The correct options are
A He was an officer in the Libyan Army during the rule of King Idris
B The 1969 coup d'état led by Gaddafi ousted King Idris
Muammar Gaddafi was an officer in the Libyan Army during the rule of King Idris. Gaddafi and some other officers in the Army were against the rule of King Idris, and the concentration of wealth in his hands. Around 70 Libyan officers united under the banner of the “Free Officers Movement”.
One fine day, King Idris was off to a Turkish spa to have his leg treated for an ailment. The Free Officers Movement seized this opportunity. They conducted a bloodless coup and overthrew the monarchy in Libya. Libya was then declared a socialist republic.