Imagine a system where a finch feeds on thistle seeds and the finch population size is linked to the productivity of the thistle, and the thistle population size is related to foraging pressure of the finch population. this is an example of population dynamics at the level. (a) population. (b) community. (c) ecosystem. (d) species.

Community.

Explanation:

Community may be defined as a group of population of two or more different species in a ecosystem. These population occupy the same geographical area and may or may not share the same resources.

The finch feeds on thistle population and the thistle population size is related to foraging pressure of finch population. Here, two populations are interacting with each other, this is a case of community.

Thus, the correct answer is option (B).

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."