Which of the following is generally defined as the difference between the brightest color (white) and
the darkest color (black)?

A.
Reconnaissance

B.
Characterizing

C.
Pixel aspect ratio (PAR)

D.
Contrast ratio

Explanation:
The contrast ratio is a measure of a display system, defined as the ratio of the luminance of the
brightest color (white) to that of the darkest color (black) that the system is capable of producing. A
high contrast ratio is a desired aspect of any display, but with the various methods of measurement
for a system or its part, remarkably different measured values can sometimes produce similar
results. Contrast ratio ratings provided by different manufacturers of display devices are not
necessarily comparable to each other due to differences in method of measurement, operation, and
unstated variables.
Answer option C is incorrect. Pixel aspect ratio (PAR) is a mathematical ratio that describes how the
width of pixels in a digital image compares to their height. Most digital imaging systems describe an
image as a grid of very small but nonetheless square pixels. However, some imaging systems,
especially those which must maintain compatibility with Standard-definition television motion
pictures, define an image as a grid of rectangular pixels in which the width of the pixel is slightly
different from that of its height. Pixel Aspect Ratio describes this difference.
The Pixel Aspect Ratio value is used mainly in digital video software, where the motion pictures are
to be converted or reconditioned so that they are used in other video systems than the original. The
video player software may use pixel aspect ratio to properly render digital video on screen. The
video editing software uses Pixel Aspect Ratio to properly scale and render a video into a new
format.

Answer option A is incorrect. Reconnaissance is a term that refers to information gathering
behaviors that aim to profile the organization, employees, network, and systems before an attack is
performed efficiently. It is the first step in the process of intrusion and involves unauthorized
discovery and mapping of systems, services, or vulnerabilities. These discovery and mapping
techniques are commonly known as scanning and enumeration. Common tools, commands, and
utilities used for scanning and enumeration include ping, telnet, nslookup, rpcinfo,
File Explorer, finger, etc.
Reconnaissance activities take place before performing a malicious attack. These activities are used
to increase the probability of successful operation against the target, and to increase the probability
of hiding the attacker’s identity.
Answer option B is incorrect. Characterizing is a term used to describe how a particular device
currently reproduces color. Characterizing is also known as profiling. Once you have calibrated a
device, it is profiled. The profile is a record of how a particular device matches with an objective
standard for color reproduction so that it can produce most accurate results possible.
Reference:
“http://en.wikipedia.org/wiki/Contrast_ratio”