I am like 99% sure its organ , try that and see if it works :)
They lose aater when it evropares but at the same time they gain water when it rains
The discipline which would be responsible for collecting data about currents and tides is oceanography. It is a study of all the changes and aspects of the ocean. It analyses, collects and monitors information that refers to the dynamic of all the natural processes that take place in the ocean, including ocean currents, waves, and geophysical processes.
Its C. Whenever you perform an experiment you want to make sure its as controled as it can possibly be.