Task: Question Answering
Input (English): Question: The reaction in which a vinyl halide or aryl reacts with a terminal alkyne in the presence of cuprous iodide and a Pd (0) catalyst is known as the reaction of: 
 Options:  <1> Suzuki <2> Heck <3> Stille <4> Sonogashira. <5> Sharpless.
Output (English): 4