Polices are ever evolving process that requires updating. Polices must change as the goals, functions and responsibilities of a company, government or employee changes. A simple policy exception could be - No unauthorized person or persons can enter the computer room. The Exception would be - Unless cleared by management and escorted by an authorized individual. In some cases there are NO exceptions - An example: Military TOP Secret information can ONLY be handled by someone with a TOP Secret Clearance; thus answer A is incorrect.

TFTP (Trivial File Transfer Protocol) is sometimes used to transfer configuration
files from equipments such as routers but the primary difference between FTP and TFTP is that
TFTP does not require authentication. Speed and ability to automate are not important.
Both of these protocols (FTP and TFTP) can be used for transferring files across the Internet. The
differences between the two protocols are explained below:
FTP is a complete, session-oriented, general purpose file transfer protocol. TFTP is used as a
bare-bones special purpose file transfer protocol.
FTP can be used interactively. TFTP allows only unidirectional transfer of files.
FTP depends on TCP, is connection oriented, and provides reliable control. TFTP depends on
UDP, requires less overhead, and provides virtually no control.
FTP provides user authentication. TFTP does not.
FTP uses well-known TCP port numbers: 20 for data and 21 for connection dialog. TFTP uses
UDP port number 69 for its file transfer activity.
The Windows NT FTP server service does not support TFTP because TFTP does not support
authentication.
Windows 95 and TCP/IP-32 for Windows for Workgroups do not include a TFTP client program.
Ref: http://support.microsoft.com/kb/102737

Logical or technical controls involve the restriction of access to systems and the protection of information. Examples of these types of controls are encryption, smart cards, access lists, and transmission protocols.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the
Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 33

The goal of a noninterference model is to strictly separate differing security levels to assure that higher-level actions do not determine what lower-level users can see. This is in contrast to other security models that control information flows between differing levels of users, By maintaining strict separation of security levels, a noninterference model minimizes leakages that might happen through a covert channel.
The model ensures that any actions that take place at a higher security level do not affect, or interfere with, actions that take place at a lower level. It is not concerned with the flow of data, but rather with what a subject knows about the state of the system. So if an entity at a higher security level performs an action, it can not change the state for the entity at the lower level.
The model also addresses the inference attack that occurs when some one has access to some
type of information and can infer(guess) something that he does not have the clearance level or
authority to know.
The following are incorrect answers:
The Bell-LaPadula model is incorrect. The Bell-LaPadula model is concerned only with
confidentiality and bases access control decisions on the classfication of objects and the
clearences of subjects.
The information flow model is incorrect. The information flow models have a similar framework to
the Bell-LaPadula model and control how information may flow between objects based on security
classes. Information will be allowed to flow only in accordance with the security policy.
The Clark-Wilson model is incorrect. The Clark-Wilson model is concerned with change control
and assuring that all modifications to objects preserve integrity by means of well-formed
transactions and usage of an access triple (subjet - interface - object).
References:
CBK, pp 325 - 326
AIO3, pp. 290 - 291
AIOv4 Security Architecture and Design (page 345)
AIOv5 Security Architecture and Design (pages 347 - 348)
https://en.wikibooks.org/wiki/Security_Architecture_and_Design/Security_Models#Noninterference
_Models