Athermometer is placed in water in order to measure the water’s temperature. what would cause the liquid in the thermometer to drop?

The hotter it gets, the faster the molecules are moving. Making the molecules further apart. The cooler it gets, the slower the molecules move, allowing them to get closer together. Does that help at all?

The correct answer is  "c".  it is "c" because melting is an endothermic change, and endothermic get's energy from surroundings.