I can't tell from the image. But, if K is in both plane IGK and P, then the answer is probably KG. However, if K is only in IGK plane, then more information is needed so none of the above.
DG is a line only in plane P and IJ is a line only in plane P so A/B are not answers.
262.6/300% for the first 3 test if you were to add another test it would be 400% total and you need 360% of test grades to have an average of 90% and so 360 - 262.6 = 97.4%