Which of the following tributaries of the Indus River flows through the Indian state of Himachal Pradesh?

Introduction / Context:
This question belongs to the chapter on Indian river systems and asks about a tributary of the Indus River that flows through Himachal Pradesh. Understanding the course of Himalayan rivers, their tributaries and the states they pass through is critical for questions on agriculture, hydropower and regional planning. The Sutlej, Beas and Ravi are all part of the larger Indus basin but their exact statewise routes can confuse learners.

Given Data / Assumptions:
- The main river system under discussion is the Indus River.
- We are concerned only with tributaries that flow through Himachal Pradesh.
- The options include Sutlej, Beas, Ravi, Hunza and Shyok, all associated with the northwestern Himalayan region.
- The question expects the standard exam key answer commonly used in Indian geography texts.

Concept / Approach:
The traditional exam perspective highlights the Sutlej as the major Indus tributary flowing through Himachal Pradesh. The Sutlej originates in Tibet near Lake Rakshastal, enters India near Shipki La, flows through Himachal Pradesh, then crosses Punjab and ultimately joins the Indus in Pakistan. While Beas and Ravi also form part of the Indus system and have segments touching Himachal Pradesh, many school-level questions single out the Sutlej as the significant Indus tributary path through the state, especially in the context of large hydropower projects such as Bhakra and Nathpa Jhakri.

Step-by-Step Solution:
Step 1: Recall that the Sutlej is one of the five rivers of Punjab and an important tributary of the Indus.Step 2: Remember the route of the Sutlej: it comes from Tibet, enters Himachal Pradesh, flows through the state and then enters Punjab.Step 3: Note that several major dams like Bhakra and Nathpa Jhakri are associated with the Sutlej in Himachal and nearby regions.Step 4: Hunza and Shyok are Indus tributaries mainly in the northern areas beyond India's current administrative control, so they do not flow through Himachal Pradesh.Step 5: Although Beas and Ravi are also Himalayan rivers, the standard single-answer exam key typically emphasises Sutlej as the major Indus tributary that flows through Himachal.Step 6: Therefore, the best answer that matches typical textbooks is Sutlej.

Verification / Alternative check:
A quick map-based check helps. On a physical map of North India, trace the Sutlej from Tibet through Himachal Pradesh and into Punjab, where it later contributes to the Indus system. Atlases and geography texts highlight the Sutlej valley as a major hydropower corridor in Himachal Pradesh. Beas and Ravi are also present in and around Himachal Pradesh but are often described separately as rivers of the Indus system flowing mainly through Himachal and Punjab, while Hunza and Shyok are drawn across the border. Since this is a single-choice question, following the most conventional key, Sutlej is the correct option.

Why Other Options Are Wrong:
Beas: A significant river in Himachal and Punjab, but exam keys usually focus on Sutlej when a single Indus tributary for Himachal is asked in this format.
Ravi: Also part of the Indus basin, yet not the standard textbook example highlighted for this specific question style.
Hunza: A tributary of the Indus located mainly in the northern areas outside Himachal Pradesh.
Shyok: Another Indus tributary flowing through high altitude areas including parts of Ladakh, not through Himachal Pradesh.

Common Pitfalls:
Many learners get confused because Beas and Ravi also connect to the Indus system and flow through or near Himachal Pradesh. In some advanced contexts, multiple rivers could arguably fit, but basic exam practice typically expects one widely accepted textbook answer. The safe strategy is to memorise the Sutlej as the single highlighted tributary of the Indus flowing through Himachal Pradesh when the question provides a single-correct format like this.

Final Answer:
Sutlej