The first inhabitants of southeast asia settled in

(a. river valleys and coastal plains

(b. forests and paddies

(c. monasteries and temples

(d. large kingdoms

The correct answer is option (a. river valleys and coastal plains.

Explanation:

To this day, the origin of Southeast Asian society remains a bit uncertain, since they have a great genetic variety.

The only fact that the theories of their origins share is that they come from Africa.

Focusing on the theory that speaks of the people of Southeast Asia being hunter-gatherers, it is believed that they have populated these lands developing agricultural activities.

We must also analyze the fact that the most populated cities arose from the places where there was more fertile land. These places were the coastal plains and valleys of the great rivers.

The inhabitants took advantage of the fertility of these lands to start an Irrigated rice crop, which later became the basis of their economy.

These crops were highly productive, and generated a lot of labor. The cultivation of rice continued until today, and today is indispensable for Asian cuisine.