Well with blocked vessels, lets use plaque buildup as the reason for blocked vessels. It's Like trying to match together two puzzle pieces that don't fit. The piece if forced together, will be a tight fit much like how blood cells/platelets trying to fit through a small area. The pressure will be increase because the more pressure that is being put on will help to push blood through a clotted area.
SIDS means sudden infant death syndrome. This is the unknown cause of infants under the age of 12 months old dying suddenly in their sleep.
For this answer I would go with D. Retinalogic. It is not a vitamin.
Probably around the neck area, since the blood vessels are there. It would still be painful since you are basically gasping for air.
Its preserve,prevent and promote.