If there is a correlation between event a and event b, which of the following statement is true ?
a. event a would not happen without event b.

b. event b has something in common with event a.

c. event b took place before event a.

d. event a gave rise to event b.

The correct answer is A.

When two events are correlated, there is an statistical association between both that evidences how they tend to occur together and in the same direction (positive correlation), or together and in opposite direction (negative correlation).

Correlation does not imply causality (therefore D is discarded). It does not provide information about the order of the events, or their features either (therefore it cannot evidence that two events have common characteristics). Hence, B and C are excluded too.

they kept back from the wars and didn't want any action meaning wars.

1.the population change is near or at replacement level.

4. the birth and death rates are balanced.

6. sweden is most likely a developed country.