The typical order of steps in the scientific method is
hypothesis, theory, law
observation, law, theory, hypothesis
observation, hypothesis, experiment, conclusion
there is no rhyme or reason to how science is done

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

thats not even an aswer choice