Because if you don’t you may die or get seriously hurt. Or just the investigation will go wrong and get unclear or wrong answers
Answer - A
Semi-conservative model of replication involves the replication of DNA in all the familiar cells in such a way that each newly synthesized daughter cell contains a double helix with one new strand and one old strand.
By knocking at the bend of the knee with a small "hammer". If the leg "spasms" then the superficial reflex is in working condition. Hope this helps :)
