S1: Resources are essential for sustenance as well as for development.
S6: Conservation does not prohibit the use of resources but emphasises judicious and planned use of natural resources.
P: Over-exploitation and unplanned consumption of resources for development, however, are leading to their depletion.
Q: These consequences can be tackled by adopting resource conservation as a means to manage and save resources for a better future.
R: Such depletion has socio-economic and environmental consequences.
S: Conservation of resources means efficiently using resources that are needed now, without harming future prospects.

The correct answer is 'Option 3'.

Key Points

• S1: Resources are essential for sustenance as well as for development.
  • This sentence states the positive importance of resources.
• P: Over-exploitation and unplanned consumption of resources for development, however, are leading to their depletion.
  • The word "however" signals a shift from the positive aspect in S1 to the negative consequences of resource use – "depletion." This creates a clear contrast and logical progression.
• R: Such depletion has socio-economic and environmental consequences.
  • The phrase "Such depletion" explicitly refers to the "depletion" mentioned in P, detailing the negative outcomes of this process. This is a strong cohesive link.
• Q: These consequences can be tackled by adopting resource conservation as a means to manage and save resources for a better future.
  • The phrase "These consequences" directly refers to the "socio-economic and environmental consequences" from R, and then proposes "resource conservation" as a solution to tackle them. This establishes a clear problem-solution connection.
• S: Conservation of resources means efficiently using resources that are needed now, without harming future prospects.
  • Having introduced "resource conservation" in Q as a solution, this sentence provides a definition or clarification of what "Conservation of resources" entails.
• S6: Conservation does not prohibit the use of resources but emphasises judicious and planned use of natural resources.
  • This concluding sentence further elaborates on the concept of "conservation" introduced in Q and defined in S, adding an important nuance about its practical application.
• The sequence P-R-Q-S creates a coherent flow: stating the importance of resources (S1), identifying the problem of depletion (P), detailing its consequences (R), proposing conservation as a solution (Q), defining conservation (S), and finally elaborating on conservation's principles (S6).
   

Coherent paragraph after rearrangement:

S1: Resources are essential for sustenance as well as for development.
P: Over-exploitation and unplanned consumption of resources for development, however, are leading to their depletion.
R: Such depletion has socio-economic and environmental consequences.
Q: These consequences can be tackled by adopting resource conservation as a means to manage and save resources for a better future.
S: Conservation of resources means efficiently using resources that are needed now, without harming future prospects.
S6: Conservation does not prohibit the use of resources but emphasises judicious and planned use of natural resources.