In the context of ancient Indian literature, the word 'Gotra' is mentioned for the first time in which of the following Vedic texts?

Introduction / Context:
This question belongs to the area of Vedic literature and social institutions in early India. The term 'Gotra' is important because it later becomes a key concept in defining lineage and clan identity among Hindus, especially in matters like marriage and ritual. Knowing which Veda first uses the term gives you a chronological anchor and helps you understand how social concepts evolved from the earliest hymns onwards.

Given Data / Assumptions:

• The focus is specifically on the first textual occurrence of the word 'Gotra'.
• The options are the four main Vedas: Rigveda, Samaveda, Yajurveda and Atharvaveda.
• We assume standard scholarly consensus used in competitive examinations.
• The question is about textual mention, not about later detailed development of the institution.

Concept / Approach:
The Rigveda is the oldest of the four Vedas and consists mainly of hymns composed by different priestly families. Many basic social and religious concepts appear here in their earliest form. The word 'Gotra' appears in the Rigveda in the sense of a clan or lineage, although the full, later-developed meaning comes over time. Subsequent Vedas and later literature elaborate and refine the concept, but for exam purposes, when asked where the term 'Gotra' occurs first, the accepted answer is the Rigveda.

Step-by-Step Solution:
Step 1: Recall that the Rigveda is considered the earliest Vedic text, followed by the other three Vedas.Step 2: Remember that many foundational religious and social terms appear for the first time in the Rigveda.Step 3: The term 'Gotra' in the sense of a clan or lineage is attested in Rigvedic hymns, though its later technical usage develops gradually.Step 4: Compare the given options. Since the question explicitly asks for the first occurrence, you should select the oldest Veda in which the term is present.Step 5: Choose 'Rigveda' as the correct answer.

Verification / Alternative check:
Standard reference books and exam-oriented guides on ancient Indian history and culture state that 'Gotra' appears first in the Rigveda. This is also repeated in many MCQ collections which use the same wording as this question and give Rigveda as the correct option. Cross-checking across such sources confirms that this is the accepted answer for competitive exams.

Why Other Options Are Wrong:
Samaveda: It mainly reuses Rigvedic verses for musical and ritual purposes; it is not the first text to introduce the term.Yajurveda: Focused on sacrificial formulas and prose explanations; important, but not the earliest occurrence of 'Gotra'.Atharvaveda: Contains spells, charms and philosophical hymns, but comes later in sequence and is not the first to mention 'Gotra'.

Common Pitfalls:
Candidates sometimes get confused by the relative chronology of the Vedas or assume that a more ritualistic or later text might first mention social terms like 'Gotra'. Another mistake is to guess randomly among the four without remembering that the Rigveda is the oldest and contains many early references to clans and families. To avoid such confusion, always keep in mind the basic order and character of the Vedas and associate earliest occurrences of many key terms with the Rigveda unless specifically stated otherwise in your study material.

Final Answer:
The word 'Gotra' occurs for the first time in the Rigveda.