Final answer:
Calligraphic, organic, and dynamic lines are most likely to have varying line weight, with calligraphic lines being the primary example due to their expressive and fluid nature.
Step-by-step explanation:
The type of line most likely to have varying line weight is the calligraphic line. Calligraphic lines are characterized by their fluid, dynamic nature, often varying in thickness and intensity. These lines are quite expressive and can be seen in calligraphy, where the line quality changes with the pressure and angle of the writing instrument. This type of line imparts a lyrical or emotional quality to the artwork, creating a sense of movement and depth. The varying line weight is also used in hatching and cross-hatching techniques to depict shadows and three-dimensional forms in drawings. Such lines can imbue the artwork with a sense of texture and volume.
In works that involve representations of nature or the human form, organic lines often have varying weights. Organic lines mimic the irregular, curving forms found in the natural world and can be seen in examples such as the flowing manes in Albrecht Dürer's prints. In these depictions, varying line weights help to convey a sense of fluidity and realism.
Finally, in more abstract artistic expressions, line quality can evoke different feelings and suggest movement. Dynamic lines, which can suggest motion or tension in a composition, often utilize changes in line weight to enhance the visual impact and direct the viewer's eye throughout the work of art.