If you are lost in the mountains, stay calm in the face of darkness, loneliness, and the unknown. It will greatly increase your chances of survival. Many people think that   preparing necessary equipment and knowing how to use it are very important, but in fact eighty percent of mountain survival is your reaction  to fear. Finding a hiding place Unnecessary labor   will make you sweat and make you cold. Find a hiding place around you before trying to start your own construction. If you are in a snow-covered area, you may be able to dig a cave in deep snow for protection from the wind. You should try to hide yourself in the middle of the mountain if possible. Stay out of the valleys--- cold air falls, and the valley floor can be the coldest area on the mountain. Signal  rescuers for help The best time to signal rescuers is during the day. Signal for help from the highest point possible--- it will be easier for rescuers to see you, and any sound you make will travel farther. If you take a box of matches and a space blanket ( a special blanket for traveling ), build three smoky fires and put your blanket ---gold side facing out --- on the ground. Do not walk away It will make finding you more difficult , as search teams will be trying to follow your path and may miss you if you have gone off in a different direction. Searchers often end up finding a car with no one in it. If you get frostbitten  , do not rewarm the affected area until you are out of danger. You can walk on frostbitten  feet, but once you warm the area and can feel the pain, you will not want to walk anywhere. Try to protect the frostbitten area and keep it dry until you are rescued. According to the passage, people most probably fail to survive if they   _
do not take enough equipment stay in the middle of the mountain do not keep themselves warm stay in a snow-covered area
Question: If you are lost in the mountains, stay calm in the face of darkness, loneliness, and the unknown. It will greatly increase your chances of survival. Many people think that   preparing necessary equipment and knowing how to use it are very important, but in fact eighty percent of mountain survival is your reaction  to fear. Finding a hiding place Unnecessary labor   will make you sweat and make you cold. Find a hiding place around you before trying to start your own construction. If you are in a snow-covered area, you may be able to dig a cave in deep snow for protection from the wind. You should try to hide yourself in the middle of the mountain if possible. Stay out of the valleys--- cold air falls, and the valley floor can be the coldest area on the mountain. Signal  rescuers for help The best time to signal rescuers is during the day. Signal for help from the highest point possible--- it will be easier for rescuers to see you, and any sound you make will travel farther. If you take a box of matches and a space blanket ( a special blanket for traveling ), build three smoky fires and put your blanket ---gold side facing out --- on the ground. Do not walk away It will make finding you more difficult , as search teams will be trying to follow your path and may miss you if you have gone off in a different direction. Searchers often end up finding a car with no one in it. If you get frostbitten  , do not rewarm the affected area until you are out of danger. You can walk on frostbitten  feet, but once you warm the area and can feel the pain, you will not want to walk anywhere. Try to protect the frostbitten area and keep it dry until you are rescued. According to the passage, people most probably fail to survive if they   _
A. do not take enough equipment
B. stay in the middle of the mountain
C. do not keep themselves warm
D. stay in a snow-covered area
Answer: