a. For the figures below, match the distance matrices (Fig. 1(a), 1(b) and 1(c)), where the instances in the rows/columns are sorted according to cluster labels, with the sets of points (Fig. 1(d), 1(e) and 1(f)). Each set of points contains 100 points and four clusters each of equal size. In the distance matrix, blue indicates the lowest distances and red indicates the highest distances. (10 pts)