What is the main difference between an SNMP trap and a syslog message?

What is the main difference between an SNMP trap and a syslog message?

A.
SNMP traps are secure, whereas syslog messages are not.

B.
SNMP traps are triggered during network outages, whereas syslog messages are informational
only.

C.
SNMP traps are forwarded to EMS systems, whereas syslog messages are forwarded to any
NMS system.

D.
SNMP traps are formally defined in a MIB, whereas syslog body contents are not formally
defined.

E.
SNMP traps are user-definable and vary based on vendor, whereas syslog messages are
standards-based.