Castiel Is a Psychologist Who Is Interested in Seeing How

Castiel is a psychologist who is interested in seeing how autonomic nervous system responses are related to subjective feelings of fear. Half the participants in Castiel's experiment watch a 10-minute graphic and violent video and the other half watch a 10-minute video of a baby kitten. While the participants are watching the video, Castiel gathers measurements of their skin conductance. After they finish watching the video the participants answer a questionnaire about their level of fear after watching the video as well as how they generally react to horror movies.
-Before dividing his participants into those who watched violent videos versus those who watched kitten videos,Castiel notices that the distribution of his participants' skin conductance scores appears to be normal.The distribution of these participants in terms of their skin conductance would be a ________.

A) symmetrical distribution
B) positively skewed distribution
C) negatively skewed distribution
D) a skewed distribution,but we can't tell whether it's positively or negatively skewed unless we see the graph.