$4.$ Argument: Some fettuccines are not taste sensations$,$ for no low fat recipes are taste sensations$,$ and

some fettuccines are not low fat recipes.

$4\mathrm{.}1$ The form of this argument is:

a$.$ No L are T$.$ b$.$ Some F are not T$.$ c$.$ Some F are not T$.$ d$.$ No L are T$.$ e$.$ Some F are not L$.$

Some F are not T$.$ No L are T$.$ Some F are not L$.$ Some F are not L$.$ Some F are not T$.$

Some F are not L$.$ Some F are not L$.$ No L are T$.$ Some F are not T$.$ No L are T$.$

$4\mathrm{.}2$ Which of the following substitutions proves the argument invalid?

a$.$ F$=$animal, L$=$dogs, T$=$cats b$.$ L$=$fish, T$=$mammals, F$=$cats c$.$ T$=$fish, L$=$mammals, F$=$cats

d$.$ F$=$dogs, T$=$mammals, L$=$animals e$.$ L$=$dogs, F$=$animals, T$=$fish