A diagram showing the relationships among concepts and ideas used for organizing information is called:

A. visualization.
B. concept map.
C. outline.
D. organizational chart.

is it C

It could be either B or C -- how does your textbook define the 4 terms (the 4 choices)?

Examples:

http://en.wikipedia.org/wiki/Concept_map
and
http://www.google.com/search?q=concept+map&hl=en&tbm=isch&tbo=u&source=univ&sa=X&ei=wIFMUaqfEqOXyAGw2oGgBg&ved=0CE4QsAQ&biw=1440&bih=703

http://owl.english.purdue.edu/owl/resource/544/01/
and
http://www.google.com/search?q=outline&hl=en&tbm=isch&tbo=u&source=univ&sa=X&ei=FIJMUcSXE4rOqQHXloDIDw&ved=0CEYQsAQ&biw=1440&bih=703

No, it is not C. The correct answer is B. concept map. To understand why, let's break down the options:

A. Visualization: While a concept map can be considered a form of visualization, the term "visualization" is a more general concept that refers to any visual representation of information. It does not specifically refer to the relationships among concepts and ideas used for organizing information.

B. Concept map: This is the correct answer. A concept map is a graphical representation that shows the relationships among various concepts and ideas. It is used to organize information and display connections between different elements.

C. Outline: An outline is a hierarchical structure that lists the main points and subpoints of a particular topic. While an outline can organize information, it does not visually represent the relationships among concepts and ideas.

D. Organizational chart: An organizational chart is a diagram that shows the structure and hierarchy of an organization, typically depicting positions and reporting relationships. It is not specifically focused on organizing information and displaying relationships among concepts and ideas.

Therefore, the correct answer is B. concept map.