In dicot roots,cork cambium is derived from

Intrafascicular cambium is present in between the

Assertion: In the stem,the pericycle takes an active part in secondary growth.
Reason: In dicots,the pericycle has the capacity to produce lateral roots.

Give a scientific reason: Grafting is not possible in monocots.

In which of the following does secondary growth take place?

$A$ timber merchant told a customer that the log of wood he is purchasing belongs to a $20$-year-old tree. He did so by