c. because arteries carry high pressure blood from the heart
Explanation:
Arteries carry the oxygenated blood that is pumped directly from the left ventricle of the heart. Since they receive blood from the heart, the blood pressure is higher in arteries than veins. To withstand the higher pressure of blood pumped by heart, arteries have thicker walls than the walls of veins.
In reality this is way too little information to go on, and it would be irresponsible to make any assumptions about an individual based on what was provided here alone, but for the sake of merely answering a High School Bio question:
