Among fatal plane crashes that occurred during the past 65 years, 651 were due to pilot error, 88 were due to other human error, 272 were due to weather, 611 were due to mechanical problems. and 118 were due to sabotage. Q1 Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it? Complete the relative frequency distribution below. Cause .1252; Pilot error % Other human error \"In Weather % Mechanical problems % Sabotage \"lo (Round to one decimal place as needed.) What is the most serious threat to aviation safety, and can anything be done about it'! 0 A. Pilot error is the most serious threat to aviation safety. Pilots could be better trained. O B. Mechanical problems are the most serious threat to aviation safety. New planes could be better engineered. O c. Sabotage is the most serious threat to aviation safety. Airport security could be increased. 0 D. Weather is the most serious threat to aviation safety. Weather monitoring systems could be improved