When lost fluid is not replaced adequately, dehydration can result. Correct answer: C Dehydration occurs when the body doesn't have as much water as it needs and has insufficient water to function properly. Factors that can contribute so dehydration are: the climate, the amount of physical exercise you are doing (particularly in hot weather), the diet. Early warning signs of dehydration are: feeling thirsty and lightheaded , a dry mouth , tiredness...