Which theorist promoted the idea that development is fundamentally affected by one's culture as well as their interactions with their own environment ?

The idea that development is fundamentally affected by one's culture was promoted by Lev Vygotsky of Russia.

The theory was termed the Socio-Cultural Theory. The socio-cultural theory talks about how the culture of the environment people live in influences them.

Lev Vygotsky believes that the society is responsible for developing higher learning and that the basis of learning is by interacting with people.

According to Lev Vygotsky, attitudes and beliefs affect individual learning.

Learn more about Lev Vygotsky theory here link

The theorist who promoted the idea that development is fundamentally affected by one's culture as well as their interactions with their own environment is:

Lev Vygotsky.

Explanation:

This Russian psychologist is best known for his Sociocultural Theory.  With this theory, Lev explained that parents, peers, caregivers, and the whole facet of socio-cultural influencers help a child to develop higher-order functions.  He postulated that learning is based on the richness or otherwise of the interaction with other people.  He strongly believed that children develop more when they solve problems under the guidance of a conscious adult and collaborate with other more capable peers.  He also emphasized the importance of play in the development of the child, urging teachers to ensure they provide adequate time and environment for play.

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