A is the answer to this question. In order to solve this, you need to consider Newton’s gravitational law. You just need to place all of the given data in a formula and you will most likely have this formula: 6.67*10^(-11) * 910 * 5.98*10^(24) / (9.9*10^(6))² = 370 N. You may need to get the values of G and M based on what you were taught or it can also be given to you.
Gravity is important because, without this, it will be hard for all of the planets to stay in place. You can just imagine what will happen when the earth loses its place and is not given the required light by the sun anymore. It can cause the earth to freeze over which can kill almost all of the life forms on earth including humans.