The Rajasthan Canal, a vital irrigation system in Rajasthan, commenced its initial phase of construction in the Ganganagar district. This district, situated in northern Rajasthan, holds significant agricultural importance, and the canal project was instrumental in bolstering the local farming sector.
- Option (A) Jaisalmer is incorrect; it was not involved in the first phase.
- Option (B) Barmer is also excluded from the initial phase.
- Option (C) Jodhpur is similarly not part of the first phase.
- Option (D) Ganganagar is the correct choice, as it was designated for the inaugural phase of the canal's construction.
Consequently, the accurate answer is (D) Ganganagar.