When three straight lines intersect at the same point, there are M pairs of vertex angles; when three straight lines intersect at different points, there are n pairs of vertex angles, then the relationship between M and N is () A. m=nB. m>nC. m<nD. m+n=10

When three straight lines intersect at the same point, there are M pairs of vertex angles; when three straight lines intersect at different points, there are n pairs of vertex angles, then the relationship between M and N is () A. m=nB. m>nC. m<nD. m+n=10

Because the intersection of three straight lines has nothing to do with whether they intersect at the same point, so m = n, so a