What is dehydration?
how can it causes?​

Explanation:

Dehydration is caused by not drinking enough fluid or by losing more fluid than you take in. Fluid is lost through sweat, tears, vomiting, urine or diarrhoea. The severity of dehydration can depend on a number of factors, such as climate, level of physical activity and diet

Dehydration is lack of water inside your body. Not having a plenty of water can cause illness. Some of those can lead you to death. Without water heart can't pump and cell won't flow inside your body.

your answer would be d.)