The correct option is C l2 and l4 are perpendicular
From ths given equations,We can find the slope of the lines by equating with ax+by+c=0Slope =−abSlope of line l1=43Slope of line l2=34Slope of line l3=−34Slope of line l4=−43Applying the slopes for conditions of perpendicular and parallel lines(i) l1×l2=43×34=1≠−1(False)(ii) l1=43,l4=−43l1≠l4(False)(iii) l2×l4=34×−43=−1(True)(iv) l2=34,l3=−34l2≠l3(False)Hence Option C is the correct answer.