what part of the plant absorbs the most water?? Is it the stem?

I believe this site has a better answer.

http://library.thinkquest.org/3715/root2.html

The roots absorb the most was. It is not the stem.

The part is the root .

The part of the plant that absorbs the most water is the roots. The roots have structures called root hairs that increase the surface area for water absorption. As water moves through the soil, it is absorbed by the root hairs and then transported upward through the stem to the rest of the plant. While the stem also plays a role in water transport, its main function is to support the plant and transport nutrients, rather than absorb water.