**Core Concept**
The question is testing the understanding of study design in epidemiology, specifically the type of study that involves collecting data from patients through interviews or questionnaires. This is a common method used in research to gather information about diseases, including glaucoma.

**Why the Correct Answer is Right**
The correct answer is a case-control study. In this type of study, patients with a specific condition (in this case, glaucoma) are compared to patients without the condition to identify potential risk factors. The researchers use patient interviews to collect data on family history, lifestyle, and other potential risk factors. By analyzing the data, researchers can identify associations between family history and the development of glaucoma.

**Why Each Wrong Option is Incorrect**
**Option A:** This is not a correct answer. A case-control study is not typically used to identify the prevalence of a disease, but rather to identify risk factors.
**Option B:** This is not a correct answer. A cross-sectional study involves collecting data from a population at a single point in time and is not typically used to identify risk factors.
**Option C:** This is not a correct answer. A cohort study involves following a group of people over time to identify the development of a disease and is not typically used to identify risk factors through patient interviews.

**Clinical Pearl / High-Yield Fact**
When designing a study, it's essential to consider the research question and the study population. In this case, a case-control study is a suitable design for identifying risk factors for glaucoma through patient interviews.

**Correct Answer:** C.