Final answer:
God has put all things under the feet of Christ, denoting his supreme authority over creation, which includes angels, humans, and the Church as part of Christian belief.
Step-by-step explanation:
The question is rooted in theological concepts related to Christianity. The answer to the question of what God has put under the feet of Christ is c) All things. This is derived from the biblical passages which indicate that Christ has dominion over all creation, thereby placing all things under his feet, signifying authority and sovereignty. Although angels, humans, and the Church are part of the dominion given to Christ, the most encompassing answer is all things, which includes these entities and more, as per Christian belief.
References to Christ's authority can often be depicted through religious art, where the placement of figures such as angels and humans in relation to Christ can symbolize this theological truth. In art, icons often portray Jesus Christ with symbolic elements like an orb, representing his reign over the world, combined with a cross signifying the triumph of Christianity.