Which of the Following Is Not True About the Wittig $\circ$

Which of the following is not true about the Wittig reaction?

A) triphenylphosphine reacts with 2 ^$\circ$ alkyl bromides by an S_N2 reaction to give an alkyltriphenylphosphonium bromide
B) alkyltriphenylphosphonium bromides are deprotonated by strong bases to give a phosphonium ylide
C) phosphonium ylids are nucleophilic
D) the product of the Wittig reaction is an alkyne