In the movie Interstellar, the time dilation the protagonist suffer in the water planet Miller, it's caused by the proximity of the planet with Gargantua or it's caused by the planet gravitational pull? From the beginning I thought is was caused by the black hole, but later I was reading this article and the guys said is caused by the planet. Do we have some info about this?

P.D: I don't have rep enough to create the Tag for the movie. So if anyone can do it. I sense a lot of questions about this movie are coming.