Upvote:5
Yes. Travisa is the visa service you have chosen to use. They require your passport so they can deliver it to the consulate, the consulate can use it to process your application, and so they can deliver it back to you. They won't be able to do the job without your passport.
I, of course, cannot promise that nothing will go wrong, but Travisa is a recommended service provider by the likes of Stanford University, Dartmouth, and the Government of India.