Determine which statement uses an invalid argument.

a.
if it is hot outside, then theresa will not wear a scarf and hat. theresa is not wearing a scarf and hat. therefore, it is hot outside.
b.
all practicing nurses must pass the state nursing exam. jane did not pass the state nursing exam. therefore, jane is not a practicing nurse.
c.
if it is monday, then the store opens at 10 a. m. it is monday. therefore, the store opens at 10 a. m.
d.
the public pool closes at 4 p. m. it is 7 p. m. therefore, the public pool is closed.