Final answer:
A dashed line is used to indicate the centers of objects such as columns and fixtures in engineering and architectural drawings, providing a visual guide to where the center of an object is.
Step-by-step explanation:
The correct answer to your question is a) Dashed. A dashed line is used to indicate the centers of objects such as columns and fixtures in engineering and architectural drawings.
Dashed lines are utilized in these drawings to represent the centerlines, which include the virtual lines running down the center of objects. They provide a visual guide on where exactly the center of an object is. It is a common practice in architectural and engineering drawings to show the precise central points in this way. For example, in the case of a column, a dashed line might run vertically through the center from top to bottom, allowing you to determine the mid-point of the column.
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