All these measures will augment employment oppurtunities.

constrain
restrain
diminish
circumscribe

The correct answer is: augment.

To augment something is to increase it in size, number, or amount. In this case, the measures being discussed are likely to increase the number of jobs available.

The other options are all negative words that mean to reduce or limit something. Constrain means to restrict or confine something. Restrain means to hold back or control something. Diminish means to make something smaller or less in amount. Circumscribe means to limit or restrict something.

In this case, the measures being discussed are likely to have the opposite effect, and will therefore augment employment opportunities.