Statement — “The government has decided to run all commercial vehicles on bio-fuels to save depleting fossil-fuel reserves.”\nAssumptions:\nI. It is possible to switch over from fossil fuels to bio-fuels for vehicles.\nII. Sufficient quantities of bio-fuels can be produced domestically to run all commercial vehicles.

Introduction / Context:
A decision to operate all commercial vehicles on bio-fuels requires feasibility on two fronts: technical switch-over and adequate supply. Without both, the decision would be impractical.

Given Data / Assumptions:

• Statement: Run all commercial vehicles on bio-fuels.
• Assumption I: Technical/operational switch from fossil to bio-fuels is possible.
• Assumption II: The country can produce (or reliably source) enough bio-fuel for all such vehicles.

Concept / Approach:
For a universal policy across commercial fleets, capability (I) and capacity (II) are both necessary conditions. If either fails, the policy cannot be implemented at scale.

Step-by-Step Solution:
1) Feasibility test: engine compatibility, distribution, standards → I.2) Supply test: sustainable production/availability at required volume → II.3) Since the decision is universal (“all”), both I and II must hold.

Verification / Alternative check:
Even with compatible technology, lack of fuel volume would doom the plan; conversely, abundant fuel without technical switch-over pathways is useless. Hence both are necessary.

Why Other Options Are Wrong:
Only I/Only II/Either: each omits a necessary leg. Neither: contradicts the policy’s possibility.

Common Pitfalls:
Confusing pilot feasibility with nationwide scalability. The statement targets nationwide commercial fleets.

Final Answer:
Both assumptions I and II are implicit.