The correct option is C The body is moving with uniform accelerated motion.
If the graph is continuously increasing with concave up, it implies that the body is moving with uniform accelerated motion.
If the graph is continuously decreasing with concave down, it implies that the body is moving with uniform retarded motion.
If the graph is a horizontal line, it implies that the body is moving with uniform motion.
If the graph is a decreasing inclined line, the body is moving with uniform decreasing velocity.