what is the proxy when the image quality is ✓, the encryption is ssl and the license is proprietary?
CREATE TABLE "comparison_chart" (
  "project" text,
  "license" text,
  "date" text,
  "protocol" text,
  "technology" text,
  "server" text,
  "client" text,
  "web_client" text,
  "multiple_sessions" text,
  "encryption" text,
  "authentication" text,
  "data_compression" text,
  "image_quality" text,
  "color_quality" text,
  "file_transfer" text,
  "clipboard_transfer" text,
  "chat" text,
  "relay" text,
  "http_tunnel" text,
  "proxy" text
);
SELECT "proxy" FROM "comparison_chart" WHERE "image_quality"='✓' AND "encryption"='ssl' AND "license"='proprietary';