What is the fate of primary xylem in a dicot root showing extensive secondary growth?

In dicot root showing secondary growth, cork is found

What happens to primary xylem and primary phloem during secondary growth?

What happens to primary xylem and primary phloem during secondary growth?

What happens to primary xylem and primary phloem during secondary growth?

What happens to primary xylem and primary phloem during secondary growth?

Which of the following statements is correct about a woody dicot stem which shows extensive secondary growth?

Which of the following statements is correct about a woody dicot stem which shows extensive secondary growth?