Propose an efficient synthesis for the following transformation:

Propose an efficient synthesis for the following transformation: od The transformation above can be performed with some reagent or combination of the reagents listed below. Give the necessary reagent(s) in the correct order, as a string of letters (without spaces or punctuation, such as "EBF"). If there is more than one correct solution, provide just one answer. B D t-BuOK. 1) MeMgBr; 2) H30 Na2Cr2O7, H2SO4, H2O NaOH E F G H H2, Lindlar's cat. H2, Pt TsCl, py dilute H2SO4 1 J K L 1) LiAIH4; 2) H307 DMP or PCC 1) EtMgBr; 2) H30 1) BH3-THF; 2) H2O2, NaOH