I believe that the answer is True
There are many things that can affect ocean currents. Particularly wind. Changes in temperature with air currents and tides affect it as well.
The independent variable in this experiment is the time the experiment took. This is because both the temperature and the number of cooked eggs can be affected during the process of the experiment.
Temperature of the water can be affected by the temperature of the eggs when they are first lowered into the water. This would decrease the temperature of the water, making it a depended variable.
The number of eggs cooked can be affected by the temperature. This would mean that the number of cooked eggs could differ depending on the temperature, meaning that it is a dependent variable.