Answer: d. double-blind
Explanation:
A double blind study can be define as the study in which both the researcher and participant do not know which participant is receiving a particular treatment. This method is useful as it prevents the bias in the results of the experiment.
The given situation is the example of double-blind study. Here, the participants as well as the researcher do not know which group of subject are receiving bacteria in the yogurt and which group is not receiving.
Answer:mental life; observable behavior
Explanation: Mental life has a lot to do with how psychologists focus more on the physiological research in the 1920s and 1960s, but as times goes by, they emphasize more on observable behavior. Because both mental life and observable behavior work together for a good psychological result.
Answer: Progesterone
Explanation: By stopping ovulation , that is, the release of the egg from the ovaries, pregnancy is prevented.
This is because there won't be any egg available for the sperm to fertilise.
It should be noted that this process mimics the body's natural response to pregnancy.
Round worms can as my vet said that putting a fecal sample with those worms wont harm them