A, D, and not sure but maybe E
When you expect something, but get something else, you have a reason big enough to ask new questions and start a new investigation.
Example:
If you create a tree by artificially breeding different species, and then plant it with certain expectations in width, size, bark width, leaf shape, etc. and things go differently, a new investigation might begin with a whole new load of questions.
Answer:

Hope it helped,
Happy homewok/ study/ exam!
Answer:
the maximum population size that a particular environment can support.
Explanation:
A population can be defined as the total number of living organisms living together in a particular place and sharing certain characteristics in common.
Generally, these populations may be divided into a fraction of the population (subpopulation) based on certain factors and reasons.
Population regulation can be defined as a biological process that balances limiting factors affecting the growth of a population based on density. The factors that regulate the growth of a population are divided into two (2) main categories and these includes;
I. Density-independent factors.
II. Density-dependent factors.
Density-dependent are regulating factors such as predation, diseases, and competition that affect the size of the population of living organisms through decreasing or increasing mortality and birth rate.
Furthermore, density-independent factors do not have an increasingly greater effect as a population's density increases. Thus, its effect are reduced as a population's density increases in size.
Carrying capacity is the maximum population size that a particular environment can support. The carrying capacity of an environment is denoted by the letter k.
Answer:
3. B, D
Explanation:
A primary source is an animal that eats only plants. (herbivore) A secondary source is an animal that only eats herbivores (carnivores)
B has birds; which are food for carnivores, and fruits, nuts, and blossoms; which are food for herbivores.
D has vegetables and grains; which are food for herbivores, and meat; which is food for carnivores
The other options have only food for carnivores, or only food for herbivores, so the answer is 3