Final answer:
The sports program designed by Spruit, van der Put, van Vugt, & Stam (2017) shown to improve the behavior of youth at risk for delinquency, the final reported improvement would be 'academic engagement'. This fits into the trend of positive behavioral outcomes being reported.
Step-by-step explanation:
Based on the context of the question, the research carried out by Spruit, van der Put, van Vugt, & Stam (2017) aimed at creating a sports program to promote positive behavioral traits among youth. The positive climate principles incorporated into their sports program proved to be successful in fostering improvements among youth at risk for delinquency. The improvements were visible in the participants' conduct, their acceptance of authority, resistance to social pressure and prosocial behavior. The missing term in the list is likely D) academic engagement. This is because the other options of either 'academic declines' or 'huge academic increases' do not appear to align with the continuum of behavioural improvements highlighted.
Studies from Spenser, Dupree, and Hartmann (1997) and research conducted by Marshal, M. P., & Molina, B. S. G. (2006), also affirm that sports programs can greatly improve the academic and social behavior of children and adolescents. Taking this context into consideration, it's plausible to suggest that increased 'academic engagement' would be another positive outcome of the sports program designed by Spruit, van der Put, van Vugt, & Stam (2017).
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