In early medieval Indian history, who was the father of the Chauhan ruler Prithviraj Chauhan?

Introduction / Context:
Prithviraj Chauhan is a well known ruler from early medieval North India, remembered for his conflicts with the Ghurid ruler Muhammad Ghori and for various legends. Knowing his lineage and the name of his father is part of basic dynastic history. This question asks for the name of Prithviraj Chauhans father.

Given Data / Assumptions:
- The ruler in question is Prithviraj Chauhan.
- The options provide several possible names for his father, including Someshwar Chauhan.
- Only one of these corresponds to historical tradition.

Concept / Approach:
Historical sources, including inscriptions and later narratives, identify Someshwar Chauhan as the father of Prithviraj Chauhan. Someshwar ruled over Ajmer before Prithviraj. The task is to recall this accepted genealogical fact and choose the correct name from the list.

Step-by-Step Solution:
Step 1: Remember that Prithviraj Chauhan belonged to the Chauhan dynasty ruling from Ajmer and Delhi.
Step 2: Historical accounts mention Someshwar Chauhan as his father.
Step 3: Review the options and identify Someshwar Chauhan among them.
Step 4: None of the other names are widely accepted as his father in standard history texts.
Step 5: Therefore, select Someshwar Chauhan as the correct answer.

Verification / Alternative check:
You can verify by recalling that the succession is often described as Someshwar of Ajmer followed by his son Prithviraj. Names like Vigraharaja appear in Chauhan genealogy but are associated with other rulers, not as the immediate father of Prithviraj. This confirms the identification of Someshwar as his father.

Why Other Options Are Wrong:
Option a is wrong because Jeet Chauhan is not recorded as the father of Prithviraj in mainstream historical sources.
Option b is wrong since Hayat Chauhan does not appear as his father in recognised genealogies.
Option d is wrong because Trilok Chauhan does not match the standard accounts of Prithvirajs immediate ancestry.
Option e is wrong as Vigraharaja was another notable Chauhan ruler but not the direct father of Prithviraj according to accepted lineages.

Common Pitfalls:
Students sometimes mix up the many similar sounding names in Rajput genealogies or assume that any famous Chauhan name must be the parent of Prithviraj. Another mistake is to rely on folk tales without cross checking with historical references. Keeping a brief family tree of key dynasties can help prevent such confusion.

Final Answer:
The father of Prithviraj Chauhan was Someshwar Chauhan.