The farmer should watch for breakage on the rope nearest to the tractor. This is because the tension on the rope is greatest where the force is being applied. The force of the tractor pulling on the rope is transferred to the log through the rope. The greater the force, the greater the tension in the rope.
The rope is also more likely to break where it is knotted or where there is a sharp bend. The farmer should avoid knotting the rope too tightly and should make sure that the rope is not bent sharply around any objects.
So, the farmer should watch for breakage on the rope nearest to the tractor, where the tension is greatest.
The other options are incorrect. The rope is less likely to break in the middle of the length or nearest to the log. There is no specific point in the length where the rope is more likely to break.