S_N2 Reactions of the Type, Nu^- + RL $\rarr$ Nu-R + L^-, are Favoured
A) When Tertiary Substrates Are

S_N2 reactions of the type, Nu^- + RL $\rarr$ Nu-R + L^-, are favoured

A) when tertiary substrates are used.
B) by using a high concentration of the nucleophile.
C) by using a solvent of high polarity.
D) by the use of weak nucleophiles.
E) answers b and c