12b. Suppose you wanted to understand the relationship between lymphatic metastasis and survival time adjusted for sex. Based on the information you have, which analytic method would be better suited for helping you to understand this? Justify your answer. In one sentence.[2 points]

a. Stratify Kaplan-Meier curves by age and perform log-rank tests on the age-specific curves

b. Build a Cox regression model including independent variables for both lymphatic metastasis and age.

Justify your answer: