Once all of the lightener is applied, double check the applicationand lightener if necessary.

Iwould go with a or d would be your answer

Ais the best answer

If the measure is suppose to have six beats and we need 1 note and 1 rest, we can either do a whole note with a half note rest after that since a whole note equals 4 beats and a half note rest equals 2 beats or we could do a whole note rest with a half note after that since a whole note rest is 4 beats and a half note is 2 beats