The correct answer is A) Alter course to the left until the range closes, then steer to the left of 306°T. Explanation: 1) When the range line is 309°T and you are steering 306°T, the range line is opening, indicating that you are drifting to the right of the range. To close the range, you should alter course to the left. 2) By altering course to the left, you will bring the range line back in alignment, allowing you to then steer to the left of your original 306°T course to stay on the range. 3) Options B, C, and D are incorrect because they do not correctly address the situation of an opening range line, which requires altering course to the left to close the range. 4) Maintaining course (option C) or altering course to the right (option D) would cause you to continue drifting away from the range, which is the opposite of what is required.