C. The female cone releases its seeds and new sporophytes grow.
Explanation:
During life cycle of conifers, pollen grain serves as male gametophyte that pollinate the female gametophyte. The female gametophyte is present in female cone and bears egg in archegonia. Fertilization and post fertilization events lead to seed development in female cone. The seeds are released and seed germination leads to formation of a new sporophyte.
Explanation: Photosynthesis removes CO2 from the atmosphere and replaces it with O2. Respiration takes O2 from the atmosphere and replaces it with CO2.
