When – occurs, each member of a population has an equal chance of being selected. – is when people in subsets of the population are randomly sampled. – is often used to select, in an unbiased way, small subsets of the population that are not large enough in number to be accurately measured. All three of these techniques are – sampling techniques.

When RANDOM SAMPLING occurs, each member of a population has an equal chance of being selected.

CLUSTER SAMPLING is when people in subsets of the population are randomly sampled.

OVERSAMPLING is often used to select, in an unbiased way, small subsets of the population that are not large enough in number to be accurately measured.

All three of these techniques are REPRESENTATIVE sampling techniques.

Explanation:

The above items described are sampling techniques that can be used in research methods. The scientist/researcher decides the best method to use based on the kind of work he's carrying out.

Often time, A random sampling is carried out. Also, some researches involve the use of one or more of the stages. This is known as Multi-stage sampling techniques.

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.