Lindlar's catalyst is often used for the reduction of alkynes to alkenes. ... ...

Lindlar's catalyst is often used for the reduction of alkynes to alkenes. The catalyst consists of palladium which is deposited in a finely divided state of barium sulfate, which is subsequently treated with a heterocyclic amine called quinoline. Which of the following is the most likely function of quinoline?  
(A) To speed up the reaction so that the alkyne is completely converted to its most reduced form of hydrocarbon
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 17. Alkynes