PART a All College Professors Are Teachers, So All Teachers

PART A All college professors are teachers, so all teachers are educators, since all college professors are educators.
This argument is correctly symbolized as follows: a. $\begin{array} { l } \text {All \( C \) are \( \mathrm{E} \). }\\ \text {All T are \( \mathrm{E} \)}\\ \hline\text {All C are \( \mathrm{T} \) }\\\end{array}$$\quad$ b. $\begin{array} { l } \text { All C are \( \mathrm{T} \).}\\ \text {All T are \( \mathrm{E} \). }\\ \hline\text { All C are \( \mathrm{E} \).}\\\end{array}$$\quad$ c. $\begin{array} { l } \text { All T are E}\\ \text { All C are \( T \).}\\ \hline\text { All C are E}\\\end{array}$

d. $\begin{array} { l } \text {All \( \mathrm{T} \) are \( \mathrm{E} \). }\\ \text {All C ate E. }\\ \text { All C are \( \mathrm{T} \).}\\\end{array}$$\quad$ e. $\begin{array} { l } \text {All C are \( \mathrm{T} \). }\\ \text { All C are E.}\\ \text {All T are \( \mathrm{E} \). }\\\end{array}$ PART B
Which of the following substitutions proves the argument invalid?
A) C = mammals, E = animals, T = fish.
B) C = cats, E = mammals, T = animals.
C) C = animals, E = mammals, T = cats.
D) C = dogs, E = animals, T = mammals.
E) C = cats, E = dogs, T = mammals.