The work area (user interface) > Selection tools > Select 2D elements
  
Select 2D elements
There are two general groups of 2D elements:
Real geometry (Geometry)
Construction geometry (Construct).
The default is to select all real and construction geometry.
Click Home and then, in the Utilities group, click Select. The Select dialog box opens. By clicking the 2D Elements heading you can display a full list of the elements including the two general groups.
By clicking one of the options, you restrict the selection to that option. For example, if you click Geometry, you restrict the selection to all real geometry (lines, circles, arcs, and so on). If you click Lines, you restrict your selection to all real lines. By double-clicking an option, you will reselect all real and construction geometry.
By clicking the 2D Elements header you can "hide" the full list.
You use the elements area to select types of 2D geometry. For example, when using Delete 2D, you can open the select tool by clicking Select and click on Lines (in 2D Elements) to select all real lines for deletion. By clicking off Lines, you will return to the general selection mode (all geometry including construction geometry) and can now click another type of geometry.
The table below outlines the full set of selectable elements.
To select all...
Click...
Real geometry
Geometry
Real lines
Lines
Real circles
Circles
Real arcs
Arcs
Specify the scope
There are three settings for the selection focus:
To select on the active workplane, click Act WP.
To select on all workplanes, click All.
To select in a specific workplane, click Sel WP, and specify the workplane.
Specify the 2D selection method
There are five selection methods for 2D elements:
All - Selects all specified elements in your choice of the active workplane or all workplanes.
Chain - Selects a chain of smoothly connected elements.
By Vertex - Selects all specified elements that connect at the vertex you click. This option will not select elements that intersect the vertex.
By Color - Selects all elements of a specified color.
By VP Frame - Selects all elements that are contained within the projection of the specified frame drawn in the viewport.
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Elements only on the active workplane can be selected by this method.
If you draw a box around partial profile areas of a workplane, the workplane is selected with the profile areas that are within the box. You can click to select other profile areas on the workplane.
By 2D Box - Selects all specified elements that lie completely within the box you specify.
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You can select a workplane using Sel WP and use the By 2D Box selection method to select 2D elements on the selected workplane (even if the workplane is not active).
Additional selection methods for features of 2D elements
Features referencing 2D elements, such as workplanes and profiles, can also be selected in the following way:
By 2D Box: Selects all features referencing 2D elements which are contained within a specified 2D box drawn in the same plane as the active workplane.
You draw a 2D box by specifying the two corner points of a frame in the active workplane. All selectable features (those referencing 2D elements) within the box are selected.