Explain simply why the Tri-State Tornado is the correct answer to: Passage: This article lists various tornado records. The most "extreme" tornado in recorded history was the Tri-State Tornado, which spread through parts of Missouri, Illinois, and Indiana on March 18, 1925. It is considered an F5, though tornadoes were not ranked on any scale in that era. It holds records for longest path length at 219 miles (352 km), longest duration at about 312 hours, and fastest forward speed for a significant tornado at 73 mph (117 km / h) anywhere on Earth. In addition, it is the deadliest single tornado in United States history with 695 fatalities. It was also the third-costliest tornado in history at the time, but has been surpassed by several others non-normalized. When costs are normalized for wealth and inflation, it still ranks third today.

Question: Based on this passage, what was the deadliest tornado in the united states?. Explanation:
To answer the above question, the relevant sentence is: In addition, it is the deadliest single tornado in United States history with 695 fatalities.