Which of the following pathways produces 2- pentanone
(1) pent-1- yne is treated with `H_(2) SO_(4) + HgSO_(4) ` and water
(2) 3- methylhex -2- ene is treated with `O_(3)` followed by hydrolysis
(3) n - butyl megnesium halide is reacted with formaldehyde
(4) hydroboration oxidation of pent -1- ene
A. `1,3`
B. `1,2`
C. `2,4`
D. `1,3,4`
