why is the BGP neighbor not in Established state?

— Exhibit —
Mar 16 18:39:15.800390 BGP RECV 172.14.10.2+57785 -> 172.14.10.1+179
Mar 16 18:39:15.800932 BGP RECV message type 1 (Open) length 59
Mar 16 18:39:15.800995 BGP RECV version 4 as 2 holdtime 90 id 192.168.5.1 parmlen 30
Mar 16 18:39:15.801064 BGP RECV MP capability AFI=2, SAFI=1
Mar 16 18:39:15.801112 BGP RECV Refresh capability, code=128
Mar 16 18:39:15.801172 BGP RECV Refresh capability, code=2
Mar 16 18:39:15.801224 BGP RECV Restart capability, code=64, time=120, flags=
Mar 16 18:39:15.801289 BGP RECV 4 Byte AS-Path capability (65), as_num 2
Mar 16 18:39:15.801705 advertising receiving-speaker only capabilty to neighbor 172.14.10.2
(External AS 2)
Mar 16 18:39:15.801787 bgp_senD. sending 59 bytes to 172.14.10.2 (External AS 2)
Mar 16 18:39:15.801845
Mar 16 18:39:15.801845 BGP SEND 172.14.10.1+179 -> 172.14.10.2+57785
Mar 16 18:39:15.801933 BGP SEND message type 1 (Open) length 59
Mar 16 18:39:15.801991 BGP SEND version 4 as 1 holdtime 90 id 192.168.2.1 parmlen 30
Mar 16 18:39:15.802054 BGP SEND MP capability AFI=1, SAFI=1
Mar 16 18:39:15.802115 BGP SEND Refresh capability, code=128
Mar 16 18:39:15.802176 BGP SEND Refresh capability, code=2
Mar 16 18:39:15.802227 BGP SEND Restart capability, code=64, time=120, flags=
Mar 16 18:39:15.802292 BGP SEND 4 Byte AS-Path capability (65), as_num 1
Mar 16 18:39:15.802615 bgp_process_caps: mismatch NLRI with 172.14.10.2 (External AS 2):
peer: <inet6-unicast>(16) us: <inet-unicast>(1)
Mar 16 18:39:15.802763 bgp_process_caps:2561: NOTIFICATION sent to 172.14.10.2 (External
AS 2): code 2 (Open Message Error) subcode 7 (unsupported capability) value 1
Mar 16 18:39:15.802913 bgp_senD. sending 23 bytes to 172.14.10.2 (External AS 2)
Mar 16 18:39:15.802969
Mar 16 18:39:15.802969 BGP SEND 172.14.10.1+179 -> 172.14.10.2+57785

Mar 16 18:39:15.803057 BGP SEND message type 3 (Notification) length 23
Mar 16 18:39:15.803113 BGP SEND Notification code 2 (Open Message Error) subcode 7
(unsupported capability)
Mar 16 18:39:15.803179 BGP SEND Data (2 bytes): 00 01
— Exhibit —
Click the Exhibit button.
Looking at the traceoptions output in the exhibit, why is the BGP neighbor not in Established
state?

A.
BGP refresh is not supported.

B.
There is a router ID mismatch.

C.
IPv6 is not supported on the local peer.

D.
The peer AS number is misconfigured.