What combination of reagents can be used to make the following substance via an enamine?

Question

Quizplus · Accepted Answer

The product shown in the image can be synthesized using an enamine as the key intermediate. Enamine can be created by reacting the carbonyl compound with a secondary amine base (such as pyrrolidine in this case) and formaldehyde. This enamine can then react with an alkyl halide (such as methyl iodide) to form the desired product. This sequence of reactions is shown in option III, thus making it the correct choice. The other options do not include the necessary combination of reagents to form an enamine, and therefore cannot form the desired product.

What Combination of Reagents Can Be Used to Make the Following