In one study described in the textbook, infants with difficult temperaments were randomly assigned to either a condition in which their mothers received sensitivity training or a condition in which their mothers received no training. In this study, infants whose mothers received sensitivity training were in the group.

The answer is an experimental group.

Explanation:

An experimental group, also called a treatment group, consists of a group that usually receives some kind of treatment during an experiment. The group is usually composed of test subjects like people, animals, plants, among others. The treatment refers to the variable that is being studied.

When the group does not get the appropriate treatment is called the control group. There is one difference between the control group and the experimental group and it could be the hypothesis you are working with.      

every society, in order to meet the needs of it's people, has to answer three basic questions:

- what should we produce?

- how should we produce it?

- for whom should we produce it?

this questions must be answered in order to, option b, aid in production decisions.

every country can't produce everything, no matter how rich their land is. it may be a matter of technology, resources or geographical conditions. so, these three questions must be resolved in order to get the most of the production of each land.

hope this !