Answer: It is A
Explanation: C and D are jokes/ complete lies. B is wrong because Darwin did observe that animals and plants adapted (evolved) to suit their environments.
ovulation
Explanation: ovulation is the release of eggs(ova) from the ovaries is the cycle of change which occurs in female reproductive system for a month.
When you shiver, that's actually how you help yourself stay warm! It's your immediate instinct reaction to do so when you're cold, so there will be more heat produced, and they occur by your muscles moving. =)
15 15
why I that awnser is 15
15