c, 22,800 (4 half lifes, 1/2, 1/4, 1/8, 1/16)
Develop plants that are unable to reproduce
By producing sterile plants, the scientists may observe the effect of their presence on the ecosystem without the risk of the plants reproducing too quickly to be controlled. If the plant does not act as an invasive specie and is promoting the ecosystem in which it is placed, non-sterile varieties of the plant may be developed. However, if the plant seems to have an overbearing competitive advantage and is easily over taking the other species' resources, it should not be introduced.
If you are talking about Alfred Wegener, then his Hypothesis was Continental Drift, a Theory that suggested that all the continents were once one large supercontinent, named Pangaea, But drifted apart from each other over a long period of time.
Answer:
The answer is C hope this helps