This is a test of commonsense. Complete the next sentence:

How to roast yams
Preheat the oven to 175 degrees centigrade (350 degrees fahrenheit).
Line a baking pan or dish with aluminium foil.
Rinse the yams with water and rub off any dirt.
Cut the yam or yams. Depending on your preferences and the size of the yam, cut the yam into fourths, sixths, or eighths.