In the DHCP process, why does the client send the DHCPREQUEST message as a broadcast?

Question $9$ options:

To increase the network's bandwidth usage.

To inform other DHCP servers it has declined their offers and to cater to cases where the server's address isn't yet known by the client.

To ensure the client's own IP address is not in use by another device.

Because the DHCP server requires all messages to be broadcasted.