The electron micrograph displays a set of human chromosomes. Which label correctly identifies each structure marked W, X and Y?
- AW: centriole, X: centromere, Y: chromatid
- BW: centriole, X: centromere, Y: microtubule
- CW: centromere, X: telomere, Y: chromatid
- DW: centromere, X: telomere, Y: microtubule