Deci and Ryan's (1985) Self-determination theory (SDT) is a prominent model of motivation and can be used to help explain and predict human behaviour. In your essay, describe each component of SDT and using relevant literature, discuss: (a) how Deci and Ryan's (1985) SDT can be used to explain students' motivation to engage in a learning environment. (b) evidence for whether SDT helps explain cultural differences in students' motivation to engage in a learning environment