The Battle of Kannauj, also known as the Battle of Bilgram, took place in 1540 between Sher Shah Suri and the Mughal Emperor Humayun. Sher Shah's decisive victory forced Humayun into exile, allowing the Suri dynasty to establish control over Northern India. This period of Mughal absence lasted for fifteen years until Humayun eventually returned to reclaim the throne in 1555.

Nasir-ud-Din Muhammad Humayun, the second Mughal Emperor, died in 1556 after falling down the stone stairs of his library, Sher Mandal, in the Purana Qila complex in Delhi. He had been observing the stars when he tripped, sustaining fatal injuries. This tragic and sudden event occurred shortly after he had regained his throne, leaving his young son, Akbar, to succeed him.

Sher Shah Suri is credited with establishing a highly efficient and systematic revenue administration during his brief reign. He introduced land measurement techniques, standardized currency, and implemented a structured tax collection system that directly benefited the peasantry and the state treasury. His administrative reforms were so effective that they served as a foundational model for the later Mughal administrative structure, particularly under Emperor Akbar, who refined and expanded upon these early innovations.

Sher Shah Suri is widely credited with establishing a robust and systematic land revenue administration during his brief reign. He implemented the 'Rai' system, which involved measuring land and assessing taxes based on productivity. His administrative reforms, including the standardization of currency and the improvement of the land revenue collection process, served as a foundational model for subsequent rulers, including the Mughal Emperor Akbar.

Humayun, the second Mughal emperor, was defeated by Sher Shah Suri at the battles of Chausa and Kannauj. He spent approximately fifteen years in exile, primarily in Persia, before gathering military support to reconquer Delhi and Agra in 1555, thereby restoring the Mughal Empire to power after a significant period of displacement.

Sher Shah Suri, the founder of the Suri Empire, introduced the silver 'rupiya' coin during his reign in the 16th century. This currency reform standardized the monetary system in India and established the foundation for the modern rupee, which remains the currency of several South Asian nations today.

Sher Shah Suri is widely recognized for his revolutionary land revenue system, which involved the systematic measurement of land and the assessment of taxes based on the actual produce. This system provided a stable financial foundation for his empire and served as a model for subsequent rulers, including the Mughal Emperor Akbar, who later adopted and refined these administrative practices to ensure efficient governance and economic stability.

Sher Shah Suri was a visionary administrator who established a highly efficient revenue and military system during his brief reign. His most enduring legacy is the reconstruction and expansion of the Grand Trunk Road, which connected major parts of the Indian subcontinent. His administrative policies, including the introduction of the silver 'rupiya', served as a foundation for later Mughal governance, particularly under Emperor Akbar.

The Mughal Emperor Babur authored the 'Baburnama', a significant historical memoir. Similarly, Emperor Jahangir wrote his own memoirs titled 'Tuzuk-i-Jahangiri'. Since both pairs 1 and 4 are accurately matched, option C is the correct choice. These works provide invaluable insights into the political, social, and personal lives of the Mughal emperors during their respective reigns.

Muhammad Shah, also known as Muhammad Shah Rangeela, was the Mughal emperor during the invasion of Nadir Shah in 1739. Nadir Shah looted the imperial treasury and seized the Peacock Throne, which was never recovered by the Mughal dynasty.