PART a If Dorothy Misses Her Plane, Then She Will $\begin{array} { l }\text { If M then } A\\ \text {A }\\ \hline\text {M }\\\end{array}$

PART A If Dorothy misses her plane, then she will arrive late for the wedding. Therefore, Dorothy will miss her plane, because she will certainly arrive late for the wedding.
This argument is correctly symbolized as follows: a. $\begin{array} { l }\text { If M then } A\\ \text {A }\\ \hline\text {M }\\\end{array}$$\quad$ b. $\begin{array} { l }\text { If M then } A\\ \text {M }\\ \hline\text {A }\\\end{array}$$\quad$ c. $\begin{array} { l } \text {If \( S \) then \( P \). }\\ \text {\text { If } A \text { then } S . }\\ \hline\text { If } P \text { then } A\\\end{array}$

d. $\begin{array} { l } \text { All \( \mathrm{M} \) are \( A \).}\\ \text { All \( \mathrm{A} \) are S.}\\ \text { All \( \mathrm{S} \) are \( \mathrm{M} \). }\\\end{array}$$\quad$ e. $\begin{array} { l } \text { \( \mathrm{S} \) are \( \mathrm{P} \).}\\ \text { \( A \) are C.}\\ \text {\( S \) are \( A \). }\\\end{array}$$\quad$ PART B
Which of the following substitutions proves the argument invalid?
A) S = George Washington committed suicide, P = he is dead, M = Abraham Lincoln committed suicide.
B) M = George Smith committed suicide, A = George Smith is dead.
C) M = Abraham Lincoln committed suicide, A = Abraham Lincoln is dead.
D) M = Abraham Lincoln is dead, A = Abraham Lincoln committed suicide.
E) M = cats, A = mammals, M = animals.