Statement–Assumption — “The State Government has unilaterally increased octroi by 5% on all commodities entering the state without seeking Central Government approval.” Assumptions: I. The State Government may be able to implement/enforce its decision. II. The Central Government may agree to support the State’s move. III. The State Government may earn considerable additional revenue from the higher octroi.

Introduction / Context:
The state announces a unilateral octroi increase. We must infer which premises make this action sensible in an intergovernmental fiscal setting.

Given Data / Assumptions:

• Octroi is a revenue instrument on goods entering a jurisdiction.
• Intergovernmental frictions may arise; central concurrence can matter (policy/legal harmony).
• Any hike is typically motivated by revenue needs.

Concept / Approach:
Two practical premises commonly underlie such moves: anticipated revenue gains (III) and an expectation—if not of prior approval—at least of eventual acquiescence or non-interference from the Centre (II), to avoid legal/political reversal. Assumption I (ability to implement) may be pragmatically true but is not strictly necessary as an assumption for the announcement; the very act of announcing represents the intent to implement, while the real strategic uncertainties concern central stance and revenue outcomes.

Step-by-Step Solution:
1) III is integral—without revenue uplift, the policy lacks fiscal rationale.2) II is reasonably implicit—states anticipate the Centre’s tolerance or support to avoid conflict.3) I, while plausible, is not the hidden premise at issue beyond the self-evident act of announcing; the decision’s success hinges more on II and III.

Verification / Alternative check:
Fiscal policy shifts usually rest on revenue expectations and higher-level alignment to sustain them.

Why Other Options Are Wrong:
“I and II” omits the core fiscal motive; “None” ignores obvious revenue expectation; “All” overstates by requiring I; “I and III” ignores Centre dynamics.

Common Pitfalls:
Treating the mere ability to implement as the key hidden premise rather than revenue/oversight dynamics.

Final Answer:
II and III are implicit