A Survey Was Designed to Study How Brook Trout Populations

Multiple Choice

A survey was designed to study how brook trout populations respond to various levels of urbanization. Urbanization had three levels: low, medium, and high impact. Historical habitats for brook trout were observed, with 200 habitats randomly selected within each level of urbanization, for a total of 600 habitats. Researchers marked each population as extirpated or present. The data are given in the following two-way table.
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$$\begin{array} { | l | l | l | l | } \hline & \text { Extirpated } & \text { Present } & \text { Total } \\\hline \text { Low impact } & 25 & 175 & 200 \\\hline \text { Medium impact } & 80 & 120 & 200 \\\hline \text { High impact } & 195 & 5 & 200 \\\hline\end{array}$$ Which of the following conclusions seems to be supported by the data?

A) The majority of habitats subject to low urbanization impact seem to be extirpated.
B) Being classified as extirpated increases a habitat's chance of being in a medium- rather than high-impact area.
C) An increase in the level of urbanization impact seems to be associated with an increase in the proportion of sites that are classified as extirpated.
D) Urbanization impact level has no effect on whether a habitat is classified as extirpated.