The flynn effect is most likely due to changes in

Explanation:

The concept of Flynn Effect refers to the change in average IQ levels of the people with the passage of time. This phenomenon was first observed by James Flynn and thats why was named after his name.

By IQ scores, the flynn effect donot means the increase in only the numbers of IQ scores or marks, it refers to an increase in the average IQ of whole population or the next generation of any population.

Reasons for change or increase in Flynn Effect :

Although Flyyn effect agrees on the fact that intelligence is something we inherit from our parents however IQ is an absolute number which can be increased because several factors affect it.

Health and Nutrition:

Studied have reported that better nutrition is the key to better health. Better health along with good services and parental care can lower the extent of IQ disabilities in children.

Education

A better and greater access to education means a more number of people can go to schools and stay for a longer periods there. This overall can have positive effects on the IQ levels of children.

Hope it help!

yes, because even though a theory has a  lot of evidence to support it, it is not always true