If your federal wages (box 1) are less than the state wages (box 16) and the reason is not another income document such as 1042-S or another W-2 form, you can choose "Other Exempt Income" and describe the exact reason for the difference. If you are unsure, you can contact your employer to confirm the reason with them.
Here is an example of how to proceed in Sprintax (Step 3 - Let's talk money):
If the difference is coming by a tax treaty exempt income, please check the following article: https://sprintaxhelp.zendesk.com/hc/en-us/articles/9435264953373-Difference-in-Federal-and-State-wages-tax-treaty-exemption