Cosider the given reaction for preparation of alkyne. (Fritsch reaction).
Anti group will migrate because of less steric hindrance.
Rate of reaction when the halide ion :
A. `I^(Θ)gtCl^(Θ)gtBr^(Θ)gtF^(Θ)`
B. `I^(Θ)gtBr^(Θ)gtCl^(Θ)gtF^(Θ)`
C. `F^(Θ)gtCl^(Θ)gtBr^(Θ)gtI^(Θ)`
D. `F^(Θ)gtBr^(Θ)gtCl^(Θ)gtI^(Θ)`