From which one of the following Indus Valley sites have archaeologists found wells within houses belonging to the mature (developed) stage of the civilisation?

Introduction / Context:
This question is from the archaeology of the Indus Valley (Harappan) Civilization and focuses on urban planning and domestic architecture. One of the striking features of this civilisation is the presence of well-planned water supply and drainage systems. The discovery of wells within houses in some sites, especially during the mature or fully developed stage of the civilisation, illustrates the high standard of urban living and civic planning achieved by the Harappans.

Given Data / Assumptions:

• The question asks from which site remains of wells within houses, belonging to the developed stage of the Indus Civilization, have been found.
• The options are Harappa, Kalibangan, Lothal and Mohenjodaro.
• We assume standard archaeological findings about major Harappan urban centres.
• The phrase 'development stage' is interpreted as the mature / fully urbanised phase.

Concept / Approach:
Mohenjodaro, one of the best excavated Indus cities, is particularly famous for its elaborate drainage system and the presence of numerous wells. Archaeologists have reported that many houses in Mohenjodaro had private wells, indicating access to water within the home and a relatively high standard of living. While other sites like Harappa and Lothal also had water management structures, Mohenjodaro is most frequently cited in textbooks for its domestic wells in the mature urban phase. Therefore, in the context of standard GK and exam questions, Mohenjodaro is the expected answer.

Step-by-Step Solution:
Step 1: Recall the main Harappan urban centres: Harappa, Mohenjodaro, Kalibangan, Lothal and others.Step 2: Focus on the feature mentioned in the question: wells found inside houses belonging to the developed urban phase.Step 3: Remember that Mohenjodaro is especially known for having many private wells, with some blocks having a well for almost every two or three houses.Step 4: While Harappa and Lothal had water structures, they are less frequently highlighted for house wells in the typical exam summaries compared to Mohenjodaro.Step 5: Kalibangan is more often associated with fire altars and ploughed fields, not primarily with house wells.Step 6: Therefore, choose 'Mohenjodaro' as the correct option.

Verification / Alternative check:
Most standard history and archaeology textbooks that describe the Indus cities emphasise Mohenjodaro's network of wells, stating that many houses had their own well or shared one nearby. This is used as evidence of an advanced level of civic amenities. Exam-focused books that include this specific question almost always provide Mohenjodaro as the key, confirming our choice as consistent with common teaching material.

Why Other Options Are Wrong:
Harappa: An important urban centre, but in exam questions about house wells in the developed stage, Mohenjodaro is more specifically highlighted.Kalibangan: Known especially for its fire altars and early ploughed field evidence; not the primary site used in textbooks for house wells.Lothal: Famous as a port city with a dockyard and warehouses; again, not the main textbook example for wells inside houses.

Common Pitfalls:
Students sometimes assume that features of one Harappan city apply equally to all sites and may guess randomly among Harappa and Mohenjodaro. Another pitfall is to over-associate Lothal with every water-related structure because of its dockyard. To avoid confusion, memorise one or two key signature features for each major site: Mohenjodaro – Great Bath and house wells; Harappa – granaries; Lothal – dockyard; Kalibangan – fire altars and ploughed fields.

Final Answer:
Wells within houses belonging to the mature stage of the Indus Valley Civilization have been prominently found at Mohenjodaro.