A controlled experiment is one that
A. proceeds slowly enough that a scientist can make careful records of the results.
B. tests experimental and control groups in parallel.
C. is repeated many times to make sure the results are accurate.
D. keeps all variables constant.
Answer:B
A controlled experiment is one that
A. proceeds slowly enough that a scientist can make careful records of the results. B. tests experimental and control groups in parallel. C. is repeated many times to make sure the results are accurate. D. keeps all variables constant.