Gaurd cells is right answer that is option C .
Hope it helps.
Problem statement is a question that comes to the mind and then stated whereas hypothesis is given after the question has been identified and the background research has been done.
Problem statement is just a question while hypothesis is an answer to the problem statement that can be proved or disproved. The experiment is carried out after the hypothesis is given in order to validate it. The data of the experiment is studied and the results are interpreted. The results then either validate the given hypothesis.
It eliminates certain genetic diseases or bad traits for the flock.
The general trend for hormones after ovulation as an individual when it approaches menstruation is that hormone levels generally rise. This increase levels of estrogen and progesterone would cause a negative feedback to the hypothalamus and the pituitary, which would result in the decline of the FSH and LH. BTW: Not to be TMI but i started mine and there is nothing to be scared of.
A and C
They both can be compared to present or past objects to show how they have changed or evolved over time