The 4- carbon compound formed during RuBP regeneration reactions of Calvin cycle is :

Question

$\begin {array} {1 1} (1)\;Sedoheptuelose\: phosphate & \quad (2)\;Xylulose\: phosphate \\ (3)\;Erythrose\: phosphate & \quad (4)\;Glyceraldehyde\: phosphate \end {array}$