Which of the following access methods is used by Ethernet?

Ethernet uses Carrier Sense Multiple Access with Collision Detection (CSMA/CD) to minimize the effect of broadcast collisions.

The following answers are incorrect:

CSU/DSU Is incorrect because Channel Service Unit/Digital Service Unit(CSU/DSU) is a digital interface normally used to connect a router to a digital circuit.

TCP/IP Is incorrect because Transmission Control Protocol/Internet Protocol(TCP/IP) is a network protocol not an access method.

FIFO Is incorrect as it is a distractor. First In, First Out (FIFO) is typically a processing methodology in which first come, first served.

Ethernet is a frame based network technology.

References:

OIG CBK Telecommunications and Network Security (pages 437 - 438)

Wikipedia http://en.wikipedia.org/wiki/FIFO