[单选题]
Three vectors, expressed ia,/4z7tascka3 a+ e wvn Cart2qzjd1ntzuc2m,o uz a 8+si8z .,be4z esian coordinates, are S = (-3.5,+4.5) T = (0,-6.5) U = (+5.5,-2.5) What is the angle of the resultant vector S + T + U measured from the positive x axis?
A. $24^{\circ}$ above
B. $24^{\circ}$ below
C. $66^{\circ}$ above
D. $66^{\circ}$ below
