Ethernet ensures that on a shared network never interfere with each other and become unreadable.

Signals.

Explanation:

Encryption is a form of cryptography and typically involves the process of converting or encoding informations in plaintext into a code, known as a ciphertext. Once, an information or data has been encrypted it can only be accessed and deciphered by an authorized user.

Some examples of encryption algorithms are 3DES, AES, RC4, RC5, and RSA.

Ethernet ensures that signals on a shared network never interfere with each other and become unreadable through the use of encapsulation and standard encryption protocols.

In Computer Networking, encapsulation can be defined as the process of adding a header to a data unit received by a lower layer protocol from a higher layer protocol during data transmission. This ultimately implies that, the header (segment) of a higher layer protocol such as an application layer, is the data of a lower layer such as a transportation layer in the Transmission Control Protocol and Internet Protocol (TCP/IP).

The TCP/IP model comprises of four (4) layers;

1. Application layer: this is the fourth layer of the TCP/IP model. Here, the data unit is encapsulated into segments and sent to the transport layer.

2. Transport layer (layer 3): it receives the segment and encapsulates it into packets and sends to the internet layer.

3. Internet layer (layer 2): packets are encapsulated into frames.

4. Network layer (layer 1): frames are then converted into bits and sent across the network (LAN).

Hence, the data unit encapsulated inside a packet is known as segment, which is typically referred to as packet segmentation.

Additionally, these data, segments, packets, frames and bits transmitted across various layers are known as protocol data units (PDUs).

answer; i believe the correct answer is (a) all trenches must have access/egress;