Statement: In India, firms with relatively high import orientation were not the ones that benefited most from Government interventions during the peak of the import-substitution era.\nAssumptions:\nI. Highly import-oriented companies do not need Government support.\nII. Companies with lower import orientation received more Government support/benefit.\nIII. Import-oriented companies are affected by Government price-related actions.\nIV. Exporting performance is affected by Government actions.

Introduction / Context:
The statement contrasts benefit distribution under import-substitution policies: the firms that were most import-oriented were not the primary beneficiaries of Government interventions. We must identify the minimal assumption that makes this comparative claim meaningful.

Given Data / Assumptions:

• Policy context: "heydays of import substitution" implies Government interventions (tariffs, quotas, licensing) favor domestic sourcing over imports.
• Observation: high-import firms were not the major beneficiaries.

Concept / Approach:
If high-import firms were not the largest beneficiaries, it follows that firms with comparatively lower import orientation benefited more. This is a necessary comparative complement; otherwise the statement lacks a meaningful contrast group.

Step-by-Step Solution:
1) The statement is about relative benefit: group A (high import) did not benefit the most.2) For this to be informative, some other identifiable group must have benefited more; the natural contrasting group is lower import orientation (Assumption II).3) Assumption I ("do not need support") is not necessary; need and receipt are different.4) Assumption III about price effects is not directly entailed; interventions during import substitution were often non-price trade barriers.5) Assumption IV about exports is off-topic.

Verification / Alternative check:
The logic of "not the ones that benefited most" minimally requires that others (plausibly low-import firms) benefited more; otherwise the partition is unintelligible.

Why Other Options Are Wrong:

• Only I: Conflates need with benefit.
• Only III: Not implicated by the claim.
• None: Denies the necessary comparative complement.
• II and IV: IV is irrelevant.

Common Pitfalls:
Assuming content about pricing or exports that is absent; the statement is purely about relative benefit across import-orientation categories.

Final Answer:
Only assumption II is implicit.