Question

which experiment should be conducted as a field investigation? observing changes in the nesting behavior of wood ducks measuring the fermentation rate of yeast in salt water determining the germination rate of a new soybean hybrid investigating gene expression in fruit fly offspring

Explanation:

Field investigations involve studying subjects in their natural environment. Observing wood - duck nesting behavior would occur in the wild (their natural habitat). Measuring yeast fermentation in salt water, determining soybean germination rate, and investigating fruit - fly gene expression are more likely lab - based (controlled environment) experiments.

Answer:

A. observing changes in the nesting behavior of wood ducks