30. In the following schematic graph of a hypothetical set of RNA-seq data, the number of reads is plotted for a region of chromosome containing two genes, from samples obtained from two different tissues. Which gene (X or Y) do you think is more likely a "housekeeping" gene? Which region (1 or 2) within gene Y most likely corresponds to an exon? (A) Gene X; region 1 (B) Gene X; region 2 (C) Both genes; region 1 (D) Gene Y; region 1 (E) Gene Y; region 2