Please i need the answer im dying here ;- What happens when matter changes state? (choose one from the following :))

Its chemical properties change.
Its physical properties change.
The energy of its particles remains the same.
none of the above

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?