What is a key difference between Intrusion Detection Systems $($IDS$)$ and Intrusion Prevention

Systems $($IPS$)?$

a$)$ IDS detects and logs attacks, while IPS actively blocks them

b$)$ IDS operates at the application layer, while IPS operates at the network layer

c$)$ IDS uses encryption for secure communication, while IPS does not

d$)$ IDS requires manual intervention, while IPS is entirely automated