A stipulation or guideline that is not mandatory but can be chosen to follow.

A condition or regulation that is available to be followed if desired, but not required.

वैकल्पिक शर्त

English Usage: In the course of the training program, there is an optional rule regarding the submission of projects.

Hindi Usage: प्रशिक्षण कार्यक्रम में, प्रोजेक्ट जमा करने के संबंध में एक वैकल्पिक नियम है।