human
Question: A student performs an experiment and the results are shown below: Before- Iron filings are brown, small, and magnetic: Copper sulfate crystals are blue, brittle, and not magnetic. After- The copper formed was reddish, solid, and not magnetic: Iron sulfide solution was colorless and not magnetic. Which statement supports that a chemical reaction took place?

Choices:
A) Changes in color occurred.
B) A new substance was formed.
C) A physical change in the iron occurred.
D) The original substances were present after.
gpt
The correct answer is 1: A new substance was formed..