[填句补文]Rough estimates in the past have predicted similarly disappointing results. ________ Says Sallie Chishol， an environmental engineer from the Massachusetts Institute of Technology. “But the take-home message is the same. Ocean fertilization is not the answer to global warming.”
A、“These are newer and better models，”
B、Its opponents argue， however， that it will stop global warming.
C、Adding iron to patches of ocean can make plankton bloom temporarily.
D、As plankton die and settle on the ocean floor， their carbon is supposedly locked up in the seabed.
[填句补文]David Guterson and his wife teach their three children at home. Guterson says that his children learn very differently from children in school： ________. For example， when there is heavy snowfall on a winter day， it may start a discussion or reading about climate， snow removal equipment， Alaska， polar bears (北极熊)， and winter tourism. A spring evening when the family is out watching the stars is a good time to ask questions about satellites and the space program.
A、Some parents prefer teaching their children at home because they do not believe that public schools teach the correct religious values.
B、Learning starts with the children‘s interests and questions.
C、Interestingly， results show that home-schooled children quite often do better than average on national tests in reading and math.
D、Critics also say that most parents are not well qualified to teach their children.