B. Subgroups
<span>When constructing a dichotomous key, the first step is to look at the group of objects or organisms and separate them into two groups based on a single distinguishing characteristic. Then continue to separate each of the groups until each object has its own separate set of characteristics.</span>
Answer:
I believe the answer is C.
Explanation:
Hope my answer has helped you!
I think that it's Photosynthesis?
Answer::: Brain structures called the hypothalamus and pituitary gland control the menstrual cycle. The hypothalamus triggers the pituitary gland to make hormones that trigger the ovaries to make oestrogen and progesterone. ... Disorders of the hypothalamus, pituitary gland or ovaries can affect menstruation, causing amenorrhoea
Alveoli are found in lungs and exchamge O2 and Co2 !!
so answer is last one !!