Individuals represented by the right end of the dose/response curve (responding to doses between 30 and 40 ppm) are to the chemical. Group of answer choices

a. very insensitive
b. very sensitive
c. relatively insensitive
d. average sensitivity

Option A, very insensitive

Explanation:

A dose response curve measure the effect of a chemical or its toxicity based on the minimum concentration of a chemical that is sufficient to produce lethal effects and hence determine the safe threshold concentration. The unit of measurement is ppm and chemical toxicity is termed as LC50. The categories of toxicity and sensitivity are as follows  

Below 10 ppm – extremely toxic & extremely sensitive

10 -100 ppm – highly toxic & highly sensitive

100- 1000 ppm – moderately toxic and sensitive

1000 – 10,000 ppm – slightly toxic and sensitive

10,000-100,000 ppm- Practically nontoxic and sensitive

More than 100,000 ppm  - harmless.

Hence, option  A is correct

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