Answer : It’s C.
Cccccccccccccccccccccccccccccccccccccccc
Because the solid is soluble in water, it cannot be calcium fluoride.
This leaves us with either silver fluoride or potassium bromide, as both are soluble in water.
Upon addition of sodium sulfate, a white precipitate forms, confirming that the substance was silver fluoride as the precipitate are of silver sulfate.
One side drops into fault
Besides building teeth and bones, calcium also keeps your blood and muscles moving and helps your nerves send messages from your brain to the rest of your body. Your body can't make calcium, so you need to get it from food or supplements. While you're pregnant, try to get at least 1,000 mg of calcium every day.