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

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

A primary xylem :

A primary xylem :

What are primary phloem and secondary phloem?

What happens to primary phloem in stem after secondary growth? (a) Compresses outside and degenerates (b) Compresses inside and degenerates (c) Becomes part of secondary phloem (d) Modifies in sclerenchyma

Compare primary phloem with secondary phloem.

In dicot stems, the cells of cambium present between primary xylem and primary phloem is the

What happens to primary phloem in stem after sec growth