Only real answers please! Don't waste answer boxes please! In one or two paragraphs, describe the factors that have helped Costa Rica have a relatively stable and peaceful history.

1838 - Costa Rica becomes fully independent. 1849-59 - Under the leadership of Juan Rafael Mora, Costa Rica takes the lead in organising Central American resistance against William Walker, the US adventurer who took over Nicaragua in 1855.

Explanation: This should help

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.

d is the logical answer but im not a 100% sure