What do these two changes have in common?
water freezing into ice
dry ice sublimating and becoming a gas

 - Both are only physical changes.
 - Both are caused by cooling.
 - Both are caused by heating.
 - Both are chemical changes.
Step 1: Think about each change.
Water freezing into ice is a change of state. So, it is a physical change. The water changes from solid to liquid. But the ice is still made of the same type of matter as the liquid water.
Dry ice is solid carbon dioxide. When dry ice gets warm, it changes state and becomes carbon dioxide gas. This change of state, from solid to gas, is called sublimation.
Dry ice becoming a gas is a physical change. A change of state does not form a different type of matter.
Step 2: Look at each answer choice.
Both are only physical changes.
Both changes are physical changes. No new matter is created.
Both are chemical changes.
Both changes are physical changes. They are not chemical changes.
Both are caused by heating.
Dry ice sublimating is caused by heating. But water freezing into ice is not.
Both are caused by cooling.
Water freezing is caused by cooling. But dry ice sublimating is not.