A surgeon excises a portion of liver of the left of the attachment of the falciform ligament. The segments that have been resected are -
The portion of liver on the left side of falciform ligament is left (anatomical) lobe of liver. And in Couinaud's functional segmentation of liver, the segment number 2, 3, 4a and 4b form the left liver lobe.
Segment la and 4
Segment 1 and 4b
Segment 2 and 3
Segment 1 and 3