Studies show that the most creative engineers get their best and most useful ideas only after doodling and jotting down what turn out to be outlandish ideas. Now that many engineers do their work with computers instead of on paper, however, doodling is becoming much less common, and some experts fear that the result will be fewer creative and useful engineering ideas. These experts argue that this undesirable consequence would be avoided if computer programs for engineering work included simulated notepads that would allow engineers to suspend their "serious"work on the computer, type up outlandish ideas, and then quickly return to their original work. Which one of the following is an assumption on which the experts' reasoning depends? ['No engineers who work with computers keep paper and pencils near their computers in order to doodle and jot down ideas.', 'The physical act of working on paper is not essential in providing engineers with the benefits that can be gained by doodling.', 'Simulated notepads would not be used by engineers for any purpose other than typing up outlandish ideas.', 'Most of the outlandish ideas engineers jot down while doodling are later incorporated into projects that have practical applications.']