Which defensive technique involves the server sending a wrong syn+ack to the client, so the client sends and rst packet notifying the server of an error? this makes the server think the client request is legitimate.
a. stack tweaking
b. rst cookies
c. syn cookies
d. man in the middle

RST cookies.

Explanation:

When the first request is sent from a sender the server sends a SYN+ACK that is invalid.This results in client generating a RST packet that lets the server know that something is not right.This makes the server think that the request sent by the client is legitimate.

Hence the answer is option B.

answer; question (1) answer; proximity;

                      question (2); // alignment;

i'm so sorry that's not a question and this isn't an answer