**Core Concept**
The Kaplan Meier method is a non-parametric statistic used for estimating the survival function from lifetime data. It is commonly employed in medical research to analyze the time to event (e.g., time to disease recurrence or death) in the presence of censored data.

**Why the Correct Answer is Right**
The Kaplan Meier method is a product-limit estimator that accounts for right-censored data by using the risk set at each time point. It calculates the probability of surviving past a particular time point by iteratively removing individuals who have experienced the event (e.g., death) from the risk set. This method is widely used in clinical trials and observational studies to estimate the probability of event-free survival.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the Kaplan Meier method is specifically designed for time-to-event data, not for analyzing continuous outcomes like blood pressure or blood glucose levels.
**Option B:** This option is incorrect because the log-rank test is a statistical test used to compare the survival distributions between two or more groups, but it is not the method used to estimate the survival function itself.
**Option C:** This option is incorrect because the Cox proportional hazards model is a regression model used to analyze the relationship between covariates and the hazard rate, but it is not the method used to estimate the survival function.

**Clinical Pearl / High-Yield Fact**
When using the Kaplan Meier method, it's essential to consider the effect of censored data on the estimated survival function. Censored data can lead to biased estimates if not handled properly, and the Kaplan Meier method provides a robust way to account for this type of data.

**Correct Answer: C. Kaplan Meier method is used for estimating the survival function from lifetime data.