When conducting a stain of chromosomes, certain regions along the chromosome will stain more darkly than the rest. This is due to the fact that these regions are more tightly condensed. What is the functional outcome of having one region more condensed (heterochromatin) than the rest (euchromatin)?

• A. Heterochromatin is typically not transcribed/transcribed at a lower rate because the tight packing limits accessibility to polymerases.
• B. Heterochromatin is transcribed at a high frequency because there are a high number of genes in a small area.
• C. Heterochromatin does not contain any genes and is a structural component of the chromosome.
• D. Heterochromatin unpacking requires many ATP and is energetically expensive.