Correct Option (B)
The passage indicates that climate change may necessitate shifting existing crop locations due to:
- Water availability and temperature suitability at other locations: The passage explicitly states, "it may also be necessary to shift the locations where these crops are grown, in response to temperature changes as well as to water availability." This directly supports statement 2.
- Poor productivity of crops: The passage mentions that "Some crops may respond favourably to the changing conditions, others may not." This implies that crops experiencing unfavorable responses, leading to reduced or poor productivity under altered climatic conditions, would necessitate relocation. This supports statement 3.
Incorrect Options:
- Melting of glaciers (Statement 1): The passage mentions that "water run-off from the Himalayas is predicted to increase over the next 30 years as glaciers melt but then decline substantially thereafter." While glacier melt affects water availability, it is presented as an underlying factor contributing to changes in water availability, rather than a direct, independent cause for shifting crop locations separate from the broader context of water availability (covered in statement 2).
- Wider adaptability of crop plants (Statement 4): This statement contradicts the premise of shifting locations. If crop plants possessed wider adaptability, they would be less susceptible to climate change impacts and less likely to require relocation. The passage highlights the need for adaptation and flexibility due to specific and potentially adverse impacts, which suggests a limitation in current crop adaptability for some crops under changing conditions.