S_N1 Reactions of the Following Type: Nu:^- + R-X $\rightarrow$ R-Nu + :X^-
Are Favored:
A) by the Use of R-Nu

Multiple Choice

S_N1 reactions of the following type: Nu:^- + R-X $\rightarrow$ R-Nu + :X^-
Are favored:

A) by the use of tertiary substrates (as opposed to primary or secondary substrates) .
B) by increasing the concentration of the nucleophile.
C) by increasing the polarity of the solvent.
D) by use of a strong base.
E) by more than one of the above.