Who led the Arab forces that conquered Sind in 712 AD, marking the beginning of Muslim rule in parts of the Indian subcontinent?

Introduction / Context:
This question tests your knowledge of the very early phase of Muslim expansion into the Indian subcontinent. The conquest of Sind in 712 AD is considered one of the first major episodes of this interaction. Recognising the name of the Arab general who led this campaign helps you build a clear chronological sequence from early Arab raids to later Ghaznavid and Ghurid invasions and then to the Delhi Sultanate.

Given Data / Assumptions:

• The year mentioned is 712 AD.
• The region concerned is Sind (in present-day Pakistan).
• The options list well-known figures associated with later invasions: Mahmud of Ghazni, Muhammad bin Qasim, Muhammad Ghori and Qutb-ud-din Aibak.
• We assume the standard narrative of early Islamic expansion into Sind.

Concept / Approach:
The conquest of Sind in 712 AD was carried out by the Arab Umayyad forces under the command of Muhammad bin Qasim. This campaign brought parts of Sind and Multan under the control of the Umayyad Caliphate. Although the political impact within the subcontinent remained limited for some centuries, the event is important as an early contact between Indian society and the Islamic world. Mahmud of Ghazni, Muhammad Ghori and Qutb-ud-din Aibak all belong to later centuries and different political entities (Ghaznavid and Ghurid kingdoms and the Delhi Sultanate).

Step-by-Step Solution:
Step 1: Associate the year 712 AD with the earliest large-scale Muslim military expedition into Sind.Step 2: Recall that this expedition was commanded by the young Arab general Muhammad bin Qasim, working under the Umayyad Caliphate.Step 3: Recognise that Mahmud of Ghazni conducted repeated raids into north-western India around the 11th century, much later than 712 AD.Step 4: Remember that Muhammad Ghori's campaigns in the late 12th century led to the defeat of Prithviraj Chauhan and opened the way for the Delhi Sultanate.Step 5: Note that Qutb-ud-din Aibak, originally a slave general of Ghori, later founded the Slave (Mamluk) dynasty in Delhi; he did not conquer Sind in 712 AD.Step 6: Therefore, the correct answer must be Muhammad bin Qasim.

Verification / Alternative check:
Standard Indian history textbooks state that in 712 AD, Muhammad bin Qasim defeated the local ruler, often identified as Raja Dahir, and brought Sind under Arab rule. This fact is repeated in almost every competitive exam guide in the chapter on 'Early Arab Invasions'. Timeline charts clearly separate this event from later invasions by Ghazni and Ghori, confirming that Muhammad bin Qasim is the correct choice.

Why Other Options Are Wrong:
Mahmud of Ghazni: Conducted numerous raids into India between roughly 1000 and 1027 AD; not associated with the 712 conquest of Sind.Muhammad Ghori: Fought decisive battles like Tarain in the late 12th century; his campaigns are centuries later than 712 AD.Qutb-ud-din Aibak: A general of Ghori who later became Sultan of Delhi; again, his career belongs to the late 12th and early 13th centuries, not 712 AD.

Common Pitfalls:
A common mistake is to see familiar names like Mahmud of Ghazni or Muhammad Ghori and choose them because they are more frequently discussed. Another error is to treat all Muslim invasions of India as if they belong to one time period. To avoid such confusion, remember a simple sequence: early Arab conquest of Sind (712 AD) under Muhammad bin Qasim; Ghaznavid raids (11th century) under Mahmud of Ghazni; Ghurid conquests (late 12th century) under Muhammad Ghori; and then the Delhi Sultanate under Aibak and others.

Final Answer:
The conquest of Sind in 712 AD was led by the Arab general Muhammad bin Qasim.