When I called at his home the other day,I found him sitting

When I called at his home the other day,I found him sitting on an armchair,________ in his hands.A
When I called at his home the other day,I found him sitting on an armchair,________ in his hands.
A.buried his head B.burying his head
C.his head burying D.his head to be buried
为什么不选c 独立主格?