A main difference between Sport Development $($SD$)$ and Sport for Development and Peace $($SDP$)$ is:

A$.$

SD focuses on preparing athletes to compete, while SDP focuses on human rights through the practice of sport.

B$.$

SD can take place in any country, while SDP initiatives focus mostly on third$-$world countries.

C$.$

SD relates to 'sport for the sake', while SDP relates to 'sport for good'.

D$.$

All of the above.