Concept:The nucleus is the membrane-bound organelle that stores the cell's genetic instructions.
Explanation:The nucleus is the control centre of the cell. It contains chromatin and chromosomes, which are composed of
DNA (deoxyribonucleic acid).
DNA is the organic molecule responsible for storing hereditary traits, such as eye colour and blood group.
It also directs the day-to-day metabolic activities of each cell through the synthesis of messenger molecules.
RNA is produced inside the nucleus by transcription, but it moves out to the cytoplasm to perform protein synthesis, so it is not permanently held there.
ATP is the energy currency of the body. It is not stored in the nucleus because it is generated in the mitochondria and consumed by active processes in the cytoplasm.
Hence, the key organic molecule that remains in the nucleus is
DNA.
Answer:A.
DNA