Which of the following procedures as routine technique for karyotyping using light microscopy

A karyotype is a photographic representation of a stained metaphase spread in which the chromosomes are arranged in order of decreasing length. With the widely used Giemsa stain (G banding) technique, each chromosome set can be seen to possess a distinctive pattern of alternating light and dark bands of variable width. The use of banding techniques allows identification of each chromosome, and can detect and localize structural abnormalities (Robbins Basic Pathology, 9 th edition. page : 234)