The cause and effect diagram was introduced by _______.

Concept:

• The Fishbone diagram is also known as the Ishikawa diagram as it was created by Japanese quality control expert Kaoru Ishikawa.

• The Ishikawa diagram or fishbone diagram or cause and effect diagram indicates the possible weaknesses of a work process and their causes.
• It helps managers to track down the reasons for imperfections, defects, variations, or failures.
• Ishikawa diagram is a visualization tool for categorizing the potential causes of a problem. This tool is used in order to identify a problem's root causes.
• It is a problem-solving tool that provides a systematic way to identify causal factors.
• The diagram looks like a fish's skeleton and its common uses are product design quality defect prevention to identify potential factors causing the effect. 

Explanation:

• The Fishbone Diagram is usually read from left to right and consists of bones, indicating possible causes of a problem, connected to a spine leading into the fish’s head, which symbolizes the defect or problem.
• For example, in the diagram below, the shape of a fish’s skeleton is formed by possible causes, grouped by category, for a failed inspection.
• Here, the causes are categorized by the “5 M’s” in manufacturing: machine, method, material, man/mind power, and measurement/medium.
• Using these as prompts to generate hypotheses for the root cause of a problem, you write the potential causes under each of these on the “ribs” of the fish.
• In the image below, for example, the problem is that 12% of the product fails inspection, and one of the potential causes of this related to the materials is that screws were worn.

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Figure: Ishikawa diagram

• By visually sorting possible defect causes, identifying cause and effect relationships, and determining which causes are having the greatest impact on the problem, the Fishbone Diagram enables people to address the problem rather than its symptoms.
• It is frequently used to aid in lean and six-sigma transformations because it allows manufacturers to reduce clutter by identifying the root causes of issues and identifying areas for improvement.
• With is information, we can say that the Ishikawa diagram represents the relationship between defects and their causes so option 3 is correct.