What is the missing reagent in the reaction below?

Question

Quizplus · Accepted Answer

The reaction involves the reduction of an alkene using sodium borohydride (NaBH4). This is a common reagent used for this type of reaction, and is already present in the reaction mixture. However, NaBH4 is not soluble in water, so it needs to be activated by adding a source of protons such as KOH or NaOH. In this case, the missing reagent is likely to be an aqueous solution of KOH (Option B) which would help to activate the NaBH4 and promote the reduction. Option A involves acetic acid which is not typically used in this type of reaction. Option C is a bare iodine which is not used as the activating agent for NaBH4. Option D is only an aqueous solution of KOH and which is likely the missing reagent for this reaction.

What Is the Missing Reagent in the Reaction Below