How Is a Root Bridge/switch Determined

How is a root bridge/switch determined?

A) All the switches in the internetwork send out hello BPDUs, and the switch that has the aggregate least number of hops to all the other switches becomes the root.
B) All the switches send out hello BPDUs, and the switch with the lowest bridge ID becomes the root.
C) All the switches send out hello BPDUs, and the switch with the highest bridge ID becomes the root.
D) The switches send out hello BPDUs, and the switch with the most direct connected switches becomes the root.
E) The core network switch becomes the root.