What is the relationship between Stratasys and 3D printing in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

27, 2015-- Stratasys Ltd. (Nasdaq:SSYS), aleading global provider of 3D printing and additive manufacturing solutions, will participate in the Prosthetics and Assistive Technology Challenge , a two-day event hosted by the VA Assistive Technology Program and VA Center for Innovation, July 28-29 in Richmond, Virginia at the Hunter Holmes McGuire VA Medical Center .

Answer: product_or_material_produced