Final answer:
The percentage of a young child's body weight comprised of water is around 70%, which is higher than in adults and reflects the child's developmental stage.
Step-by-step explanation:
The percentage of a young child's body weight that is comprised of water varies with age. While human beings are mostly water, this percentage changes from infancy to adulthood. For infants, it is typically higher, around 75 percent, and reduces to about 50-60 percent for adults.
Considering that the options provided are for young children rather than infants or adults, the correct answer would be closer to (c) 70%, which reflects the higher end of the spectrum for children who have not yet reached adulthood. The water in the child's body is not pooled in any specific area but is distributed throughout the body and involves several bodily functions, such as those carried out by the brain and kidneys, which have some of the highest proportions of water.