The loss of water in plants in the form of liquid is known as guttation. Guttation occurs when excess water is forced out of the plant`s specialized structures called hydathodes. These hydathodes are found on the leaf margins and allow water to be released as droplets. Guttation usually occurs during the night or early morning when the soil is moist, and the plant`s root pressure is high.

Transpiration, on the other hand, is the loss of water in the form of vapor from the plant`s leaves and stems. It is a vital process for plants as it helps in cooling and transporting nutrients. Osmosis is the movement of water through a selectively permeable membrane, while imbibition is the absorption of water by dry substances such as seeds or dry soil.

Therefore, the correct answer is option 3: Guttation.