Why don't terminal IDs prevent unauthorized entery?

Question

I'm studying for CISSP and had gotten this question wrong. I also found it and the correct answer online, but still don't understand the reasoning.

Source

2. Which of the following controls is not appropriate to prevent unauthorized people from entering a computer center?

a. Double-locked doors

b. Television monitors

c. Terminal IDs

d. Picture ID badges

2. c. Logical access controls verify the terminal identification (ID) number and not a part of physical security. Logical access controls provide a technical means of controlling what information users can utilize, the programs they can run, and the modifications they can make. The other three choices deal with physical security, which is the right kind of control to prevent unauthorized people from entering a computer center.

First of all, what is the definition of "controls"?

Second, I thought b) would be the correct answer because TV monitors don't actually prevent anything by themselves.

By terminal IDs do they mean the username/password a person can login to a computer with? This certainly seems ambiguous because it could also refer to a serial number used for keeping track of physical assets, or some sort badge that shows the person is allowed in.

Answer 1

Yes, I believe the terminal ID refers to a username/password, and yes it is rather ambiguous.

I think the idea it is trying to convey is that log in credentials prevent user operational access to a computer system, but do not actually prevent access to the computer itself.

Its easy to argue that TV monitors do not prevent unauthorized people from entering a computer center, and possible to argue that a "Terminal ID" could be used to verify a person before allowing phsical access. The word "Terminal" though almost universally means at least a screen with a fully fledged keyboard, as opposed to a keypad next to a locked door - and this is the only reason I would say that B is the most correct answer.

I say most correct because to me your answer is also a degree of correct. As is ID badges really. It's a poorly worded question with even poorer options to choose from.