Here's a short story: A star has a greater mass then a planet. This means the (A) star (B) planet emits a stronger gravitational field.  What is the most sensical answer between "star" and  "planet"?
star

Here's a short story: Tony used his sawblade to cut both wood and stone. He learned that cutting wood generated less heat than cutting stone. This made him realize that the _____ was less rough (A) wood (B) stone.  What is the most sensical answer between "wood" and  "stone"?
wood

Here's a short story: A stick of bamboo experiences low resistance when dragged across a pier and high resistance when dragged across a marsh. This means the _____ will cause the bamboo to heat up more (A) marsh (B) pier.  What is the most sensical answer between "marsh" and  "pier"?
marsh