Answer:
The crop failures were caused by late blight, a disease that destroys both the leaves and the edible roots, or tubers, of the potato plant. The causative agent of late blight is the water mold Phytophthora infestans. The Irish famine was the worst to occur in Europe in the 19th century.
Positive becaus Mexico city is right
Calcrete or Caliche is a type of sedimentary rock often found in arid and semiarid regions. It is composed of calcium carbonate with bits of gravel, clay and silt. It is found in Australia, Kalahari Desert, Sonoran and Mojave desert. Note that caliche does not form through dissolution and reprecipitation of rainwater. Rather, it forms when water from the ground rise above through capillary action, bringing up minerals from the ground into the surface.
The answer is: [C]: New Zealand.
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Note: the key world is "primarily".
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Australasia consists PRIMARILY of Australia and New Zealand.
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