VOCABULARY — Choose the best synonym (same meaning) of the highlighted word, based on the sentence. Sentence: “The leader nodded his APPROBATION.”

Introduction / Context:
“Approbation” is a formal noun meaning approval or praise, often used in political and ceremonial contexts. In the sentence, the leader’s nod signals consent or official approval. The task is to pick the closest everyday synonym that preserves this formal sense.

Given Data / Assumptions:

• The act is a nod from a leader, implying consent/authorization.
• We seek the best single-word replacement recognized widely by learners.
• We must distinguish between approval and related but distinct responses like appreciation or admiration.

Concept / Approach:
“Approval” is the direct synonym, especially when someone in authority signals agreement. “Appreciation” expresses grateful recognition; “admiration” expresses esteem or wonder; “understanding” signals comprehension. Only “approval” captures the institutional/authoritative yes implicit in the nod.

Step-by-Step Solution:
1) Clarify action: a nod indicating consent.2) Map to noun: approbation = approval.3) Substitute: “nodded his approval” is a common idiom.4) Exclude near-synonyms that express different emotions or cognitive states.

Verification / Alternative check:
Standard collocations include “win the approbation of,” “with the approbation of the council,” directly parallel to “with the approval of.”

Why Other Options Are Wrong:
A) “understanding” — comprehension, not consent.C) “admiration” — esteem, not authorization.D) “appreciation” — gratitude, not formal approval.

Common Pitfalls:
Picking a pleasant-sounding noun like “admiration” without checking whether it means agreement or permission. “Approbation” is about approval.

Final Answer:
approval