In the Indira Gandhi Canal Command Area (IGCCA), the left bank of the main canal is at a higher elevation. Consequently, gravity flow cannot irrigate this area, necessitating lift irrigation, which involves pumping water to the fields.
The other options are incorrect:
(A) The right bank is typically irrigated via gravity flow.
(C) and (D) are imprecise and do not specifically pertain to the canal's configuration.