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the obligate parasite requires strigolactones for seed germination and not karrikins. The plant secrete strigolactone from its root into the soil as mentioned. In the soil, strigolactone promotes the seed germination of the parasitic weed.
The strigolactones can be beneficial for the germination and growth of the weed plant.
Answer: false. It is not discarded until there is evidence against it.
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The answer is definitely A. Houses. Basing on the Demographic Transition Model (DTM), countries categorized under stage 4 are said to have a stabilized population growth in other words birth and death rates are merely low. But still gradually on increasing number. As total population increases, housing now becomes insufficient. Examples of Stage 4 countries: Brazil, China, Argentina, Singapore, U.S.