A waiting$-$line system that meets the assumptions of M$/$M$/1$ has $\backslash$lambda $=1,\backslash$mu $=4.$ For this system, what is the probability of fewer than two units in the system?

Select one:

a$.0\mathrm{.}25$

b$.0\mathrm{.}0625$

c$.0\mathrm{.}75$

d$.1\mathrm{.}00$

e$.0\mathrm{.}9375$