The correct answer is: D. to move cursor to the beginning of the line specified by the number.
The [line number G] key is a cursor movement key that moves the cursor to the beginning of the line specified by the number. For example, if you press the [line number G] key when the cursor is on line 1, the cursor will move to the beginning of line 1. If you press the [line number G] key when the cursor is on line 2, the cursor will move to the beginning of line 2.
The other options are incorrect because they do not describe the function of the [line number G] key. Option A is incorrect because the [line number G] key does not move the cursor left by one position. Option B is incorrect because the [line number G] key does not move the cursor right by one position. Option C is incorrect because the [line number G] key does not move the cursor down by one line. Option E is incorrect because the [line number G] key does move the cursor to the beginning of the line specified by the number.