In a forest, animals like voles and wood lice feed on plant roots and barks respectively. Among the other carnivores, foxes, shrews and owls are present in that forest. Following predictions are made by a group of observers who have visited the forest : 1

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Q: 112 (CDS-I/2014)
In a forest, animals like voles and wood lice feed on plant roots and barks respectively. Among the other carnivores, foxes, shrews and owls are present in that forest. Following predictions are made by a group of observers who have visited the forest :
1. If the roots of the tree develop a disease, then voles and foxes will starve and not the owls.
2. Population of voles is dependent on wood lice population through food web.
3. If owl population declines, it will indirectly affect wood lice population.
4. If barks of tree are affected due to a disease, then reduction of wood lice will affect the shrew population forcing owls to eat more voles.
Which of the above predictions is/are correct?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,1,46,22,11,6,8

keywords: 

{'wood lice feed': [0, 0, 0, 1], 'wood lice population': [0, 0, 0, 1], 'owl population': [0, 0, 0, 1], 'wood lice': [0, 0, 0, 1], 'other carnivores': [0, 0, 0, 1], 'foxes': [0, 0, 0, 1], 'owls': [0, 0, 0, 1], 'more voles': [0, 0, 0, 1], 'animals': [0, 0, 1, 2], 'shrew population': [0, 0, 0, 1], 'barks': [0, 0, 0, 1], 'forest': [9, 1, 6, 21], 'voles': [0, 0, 0, 1], 'tree': [3, 0, 1, 1], 'observers': [0, 0, 0, 2], 'shrews': [0, 0, 0, 1], 'reduction': [2, 4, 2, 13], 'predictions': [0, 0, 0, 2], 'plant roots': [0, 0, 0, 1], 'roots': [9, 2, 8, 7]}

The correct answer is option 1, which states that predictions 1, 2, and 4 are correct.

Let`s evaluate each prediction to understand why they are correct:

1. If the roots of the tree develop a disease, then voles and foxes will starve and not the owls.

This prediction is correct because voles feed on plant roots, and if the roots are affected by a disease, their food source will be reduced, leading to starvation for both voles and foxes. Owls, on the other hand, primarily feed on small mammals like voles, so they will not starve directly from the plant root disease.

2. The population of voles is dependent on wood lice population through the food web.

This prediction is correct because voles feed on plant roots, and wood lice feed on plant barks. If the population of wood lice decreases, their availability as food for voles will decrease, affecting the vole population.

3. If owl population declines, it will indirectly affect the wood lice population.

Alert - The provided answer is incorrect; prediction 3 is not mentioned in any of the options.

4. If barks of a tree are affected due to a disease, then a reduction of wood