Which of the following major Indian rivers flows from east to west and drains into the Arabian Sea, instead of flowing towards the Bay of Bengal?

Introduction / Context:
This question is about the directional pattern of major Indian rivers. Most of the large rivers in northern and peninsular India flow generally from west to east into the Bay of Bengal. However, a few important rivers flow from east to west and discharge into the Arabian Sea. Identifying these exceptions is a common theme in Indian geography questions.

Given Data / Assumptions:

• The question asks for a major Indian river that flows from east to west and drains into the Arabian Sea.
• Options are Brahmaputra, Narmada, Ganga, Krishna and Mahanadi.
• We assume standard descriptions of river courses as taught in school geography.
• No detailed coordinates are given, so the answer relies on conceptual understanding of drainage patterns.

Concept / Approach:
In India, most rivers, especially the Ganga, Brahmaputra, Krishna and Mahanadi, flow towards the Bay of Bengal. By contrast, Narmada is a prominent exception, flowing in a generally westward direction along a rift valley between the Vindhya and Satpura ranges and emptying into the Arabian Sea. Recognising Narmada as a west flowing river is essential for answering this question correctly.

Step-by-Step Solution:
Step 1: Recall the general courses of the given rivers. Step 2: Remember that Ganga, Brahmaputra, Krishna and Mahanadi all end in the Bay of Bengal after flowing broadly west to east or north to south east. Step 3: Recognise that Narmada flows through central India in an east to west direction in a rift valley and drains into the Arabian Sea. Step 4: Eliminate all rivers that are known to end in the Bay of Bengal. Step 5: Select Narmada as the only major river in the options that fits the description of a west flowing river to the Arabian Sea.

Verification / Alternative check:
Verification can be done using any physical map of India that shows river courses. Tracing each river from its source to its mouth, you will see that Narmada flows westwards and enters the Arabian Sea near the Gulf of Khambhat, while Ganga and Brahmaputra combine to form a vast delta on the Bay of Bengal side and Krishna and Mahanadi also reach the Bay of Bengal. This visual confirmation supports the textbook description that Narmada is one of the principal west flowing rivers of peninsular India.

Why Other Options Are Wrong:
Brahmaputra flows from Tibet into India and then through Bangladesh before emptying into the Bay of Bengal, not into the Arabian Sea. Ganga rises in the Himalayas and flows eastwards across northern India, draining into the Bay of Bengal via a wide delta. Krishna originates in the Western Ghats and flows eastwards through several states to reach the Bay of Bengal. Mahanadi also flows eastwards through Chhattisgarh and Odisha and enters the Bay of Bengal near its delta. None of these rivers match the pattern described in the question.

Common Pitfalls:
A common mistake is to confuse Narmada with other peninsular rivers like Krishna or Mahanadi because all originate in or near the central highlands. Another error is forgetting that the majority of Indian rivers flow into the Bay of Bengal and that only a few like Narmada and Tapi flow into the Arabian Sea. To avoid such confusion, consciously group rivers into Bay of Bengal draining and Arabian Sea draining categories during revision.

Final Answer:
Narmada