[Answer] Adventurous couples often take marriage proposing to whole new levels—literally. When Tim and Natalie go heli-skiing at Whistler in British Columbia, what threatens to upend Tim's plans to propose?

Step 1 : Introduction to the question " Adventurous couples often take marriage proposing to whole new levels—literally. When Tim and Natalie go heli-skiing at Whistler in British Columbia, what threatens to upend Tim's plans to propose? "

...1. Tim's mustache 2. a pending snowstorm 3. a helicopter maintenance problem 4. Natalie's broken ski