What do these two changes have in common?
boiling sugar to make caramel
water boiling on a stove

 - Both are only physical changes.
 - Both are caused by heating.
 - Both are caused by cooling.
 - Both are chemical changes.
Step 1: Think about each change.
Boiling sugar to make caramel is a chemical change. The heat causes the sugar to change into a different type of matter. Unlike sugar, the new matter is brown and sticky.
Water boiling on the stove is a change of state. So, it is a physical change. The liquid changes into a gas, but a different type of matter is not formed.
Step 2: Look at each answer choice.
Both are only physical changes.
Water boiling is a physical change. But boiling sugar to make caramel is not.
Both are chemical changes.
Boiling sugar to make caramel is a chemical change. But water boiling is not.
Both are caused by heating.
Both changes are caused by heating.
Both are caused by cooling.
Neither change is caused by cooling.