This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Microarray is best characterised by 
Select and explain. 
A. Study of organisms, B. Study of disease, C. Study of multiple genes, D. Study of blood group
C: Study of multiple genes
Answer: C: Study of multiple genes 
Explanation: Microarrays are gene chips used to sequence genes or portions of genes.In this technique, short sequences of DNA(oligonucleotides) that are complementary to the wild-type sequence and to known mutations are “tiled” adjacent to each other on the gene chip, and the DNA sample to be tested is hybridized to the array. Before hybridization the sample is labeled with fluorescent dyes. The hybridization (and consequently, the fluorescent signal emitted) will be strongest at the oligonucleotide that is complementary to wild-type sequence if no mutations are present, while the presence of a mutation will cause hybridization to occur at the complementary mutant oligonucleotide.