A B and F... Reproducing is required while being an organism to keep the species alive, some dont always completely go through the process but they do have a sence as a whole to do it! Obtaining energy is highly required you have to have energy to do Anything in life... and in most organisms (such as all plant and trees) sunlight has to be present for photosynthesis which is food for the plans therefore two in one because food makes energy for plants to live