1. D
This graph shows an increase in speed. At first it's slow (Tom climbing up the hill), then it's a little faster (Tom walking across the top) and then it increases more (Tom running down the hill)
2. F
This graph shows a gradual increase of speed, then the speed it's almost zero -which means that in a long interval of time Tom did very little distance- and then the speed goes up again.
3. C
In this story, Tom stopped for a moment and then sped up. In graph C there's a horizontal line at a given distance. This means that Tom stopped walking and, naturally, the time kept going on.
4. H
There's a vertical line in this graph. It means that for a given time Tom was at one distance from home and at another distance from home at the same time. That's why this graph is wrong
5. J
Distance from home = 0 means he's home. He walked all the way home, so the graph has to start at a point that's not 0 and end at distance from home = 0