Thank you SO much or Thank you VERY much?

 

Actually we have three possibilities: 1. Thank you so much 2. Thank you very much 3. Thank you a lot

I like neither. A plain and simple "thank you" is more than enough. I do not believe there are degrees in our appreciation for whatever we are thankful for. 

My students use such silly clichés, when writing emails, mainly because they copy the communications they receive from native speakers; usually ignorant native speakers. Let us rid ourselves of nonsensical clichés.