Which logical process utilizes a contraposition?

A.
If two lines are parallel, then the lines are not intersecting. Two lines are parallel. Therefore, they are not intersecting.
B.
If a line is horizontal, then the slope is zero. The slope of a line is not zero. Therefore, the line is not horizontal.
C.
If a car is working properly, then it is not in the repair shop. A car is in the repair shop. Therefore, it is working properly.
D.
If a baby is happy, then the baby is not crying. A baby is not happy. Therefore, the baby is crying.

Question

Which logical process utilizes a contraposition?

A.
If two lines are parallel, then the lines are not intersecting. Two lines are parallel. Therefore, they are not intersecting.
B.
If a line is horizontal, then the slope is zero. The slope of a line is not zero. Therefore, the line is not horizontal.
C.
If a car is working properly, then it is not in the repair shop. A car is in the repair shop. Therefore, it is working properly.
D.
If a baby is happy, then the baby is not crying. A baby is not happy. Therefore, the baby is crying.

anonymous · Answer

D

zzr0ck3r · Answer

@KingKalanikau $p\implies q \iff \sim q\implies \sim p$ 
so I woud say B.