Answer:
thinking at the margin.
Step-by-step explanation:
The thinking at the margin means to think for the next step that taken forward. Here marginal means extra
Let take an example of the marginal the first lemonade glass quenches your thirst but the next glass would quenches your thirst so much now if you think at the margin so here what would be the next action relevant for you
So as per the given situation, it is a thinking at the margin