Which of the following example(s) does NOT cause bias in a research study. A) Measuring body temperature with an oral thermometer in half of subjects and an ear thermometer in others
B) Counting the number of firefighters at your house to predict if it will be destroyed
C) Using a set of standardized questions to measure food intake in children
D) Studying workers to see the effects of a new health care law on unemployed

(A) The internal body temperature can be taken from any area of the body without a difference in the type of temperature, resulting in NO bias. Of course this is completely reliant on the type of illness, but out of all options this is correct.

Illnesses affect the throat/mouth and ear.
checking the thermometer underneath a tongue will result in the same temperature as the ear, in an ill individual.

D

Explanation:

based on my lesson when. I was in grade 6