Which Sequence of Steps Below Describes the Best Synthesis of 5-Oxohexanoic

Which sequence of steps below describes the best synthesis of 5-oxohexanoic acid starting with 1-methylcyclopentan-1-ol?

A) 1. Conc. KMnO₄
2) Dry gaseous HBr
3) mg/ether
4) CO₂
B) 1. H₂SO₄ and heat
2) Conc. KMnO₄
C) 1. Conc. KMnO₄
2) CH₃MgBr/ ether
_3. H₃O⁺
D) 1. H₂SO₄ and heat
2) O₃
3) (CH₃) ₂S
4) PCC
E) 1. H₂SO₄ and heat
2) Conc. KMnO₄
3) LiAlH₄
4) H₃O⁺