Which of the following represents a disadvantage of a hardware keylogger?

a$.$

Because of its physical nature, it can easily be visually detected and removed.

b$.$

Operating systems can easily detect the presence of a hardware keylogger.

c$.$

Installation requires physically opening the case and inserting it internally.

d$.$

It needs to be installed and retrieved without the threat actor being detected.

b$.$

Check the digital signature.

c$.$

Contact the certificate authority.

d$.$

Contact the digital signature authority.