What does it mean that a hypothesis must be testable? can a hypothesis be proven unquestionably true? why or why not?

A hypothesis must be testable because it needs to prove its veracity to be accepted. A hypothesis cannot be proved unquestionably true, because it is susceptible to errors and can present false information, which will be revealed through the tests.

Explanation:

Hypothesis is the assumption of something that may (or may not) be credible, that can be verified, from which a conclusion is drawn. Popularly, the term is used as a synonym for speculation, chance or possibility of something happening. In scientific and academic research, for example, a hypothesis corresponds to a possibility of explanation about a particular cause of study. An object of research can have several different hypotheses, and it is the responsibility of the researcher to put into practice experiences and other methods of verification to discover which hypotheses are most likely or true.

Thus, we can say that a hypothesis must be testable because it needs to prove its veracity to be accepted. A hypothesis cannot be proved unquestionably true, because it is susceptible to errors and can present false information, which will be revealed through the tests.

the answer to your question is b

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.