How does the description of the skull Peterkin finds as "large, and smooth, and round" add to the poem's ideas about war?

A.
It suggests that war is simply a necessary and unavoidable human experience.

B.
it brings many sad memories to the grandfather's mind, adding to his regrets as he describes the battle.

C.
it makes the skull sound like a toy ball, adding to the grandfather's casual view of the deaths caused by the battle.

D.
It makes the skull sound frightening, filling the children with fear about war.