It’s blurry but imma assume the last one
Oxygen i think
hope this helps
The correct answer would be nuclear energy. The other answers would be fossil fuels because they are naturally made.
These two frog species separate by reduced hybrid viability. In reduced hybrid viability gene of different parent species may interact and impair the hybrid's development while in a reduced hybrid fertility a viable individual is sterile often due to the inability to produce normal gametes in meiosis. Hybrid breakdown; the first generation are viable and fertile, but when they mate the offspring are feeble and sterile.