Need help a little stuck

C.  Studying yeast cells to learn how they divide

Explanation:

For this problem, we want to look at a topic that is a simple piece of scientific research.  Let's review each of the options provided to make this determination.

A.  Developing artificial drugs to treat cancer

This option is clearly not simple as it requires advanced knowledge of how drugs affect the body, how to build the drugs, the effects of cancer, how cancer works, etc.

B.  Researching materials to make stronger cars

This option is clearly not simple as it requires knowledge of the strength of materials, what is necessary for a car, why a car may need stronger materials, the trade-offs given by making a stronger material for a car, etc.

C.  Studying yeast cells to learn how they divide

This option is clearly a simple as you simply need to understand what cells are, what yeast cells look like, and the process by which cells duplicate.

D.  Studying rain forest plants to find medical drugs

This option is clearly not simple as it requires knowledge of the different ecosystems of a rain forest, advanced botanical knowledge used to identify different types of plants, knowledge regarding specific ailments that could be treated by drugs, and potential uses of plants to make drugs, etc.

Given this break down of each answer choice, we should choose C as our basic scientific research since it is the least involved.  Notice how all the advanced options use science to lead to the creation or discovery of something new, while the basic option simply yields an observation of knowledge.

Cheers.