The National Science Foundation has a new tool to gather information about severe weather. The tool is called a DOW (Doppler on Wheels). (1) The truck actually looks like something out of a science fiction movie. It has a huge satellite dish mounted on the back. Scientists use DOWs to track severe storms, such as hurricanes, tornadoes, and snowstorms. The mobility of these trucks allows scientists to get close and personal with a storm. This technology gives scientists an advantage that they did not have in the past. (2) For example, while scouting a severe storm on the Wyoming prairie, a DOW team spotted a cell that was just beginning to form a tornado. They stopped the truck to note the increases in wind shear and moisture, two sure signs of possible tornado development. Once the tornado did form, they moved to higher ground to continue tracking the storm. (3) Which sentence below best fits in blank #1? A. A DOW once recorded high wind speeds of over 300 miles per hour. B. A DOW is available by request to universities so students can learn about these trucks. C. DOW scientists are known as "storm chasers" because they go on the road to study twisters. D. A DOW is a truck with scientific equipment mounted on the back of it.