Suppose that you want to encrypt a single message M ∈ {0, 1, 2} using a random shared key K ∈ {0, 1, 2}. Suppose you do this by representing K and M using two bits (00, 01, or 10), and then XORing the two representations. Does this seem like a good protocol to you?

Encrypt a single message M ∈ {0, 1, 2} using a random shared key K ∈ {0, 1, 2}. No, this protocol does not seem good.

Explanation:

No, this scheme does not have the security guarantees of a one-time pad. The table below lists the  resulting encrypted messages using this scheme. We can see that some outcomes exclude certain inputs.

For example, given E(K,M) = 11 an attacker knows that the sent message M is not 0.

K M E(K,M)

00 00 00

01 00 01

10 00 10

00 01 01

01 01 00

10 01 11

00 10 10

01 10 11

10 10 00

1. entrepreneur.com

2. wikipedia

solution:

this situation is called an ip conflict.

data from a server is sent in small bits called packets. in an ip conflict, some packets will end up in one computer while some other packets will end up in another computer.

so…overall none of the computers get the data as the original message or picture being sent by the server cannot be retrieved with only half the packets. so it will show up as an error.

thus the final answer is d.