Which process is shown in the figure below?

Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening,carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of the following options.

The process by which plants lose water in liquid form is called $P$,while the process by which plants lose water in the form of vapor is called $Q$.

In terrestrial plants,guard cells differ from other epidermal cells in possessing ..........

Through which process is liquid exuded from the uninjured part of a leaf tip?

What causes the opening of stomata in plants?