How Do Volcanic Bombs Originate

How do volcanic bombs originate?

A) as high temperature residue violently expelled from the melting region, all the way up the volcanic conduit
B) as blocks of old shattered volcanic rock ejected from an erupting volcanic crater
C) as semi-molten magma blobs that get erupted, streamlined, and partly congeal before falling to the ground
D) as ash particles that join together in the eruptive plume and fall as cobble-sized objects