Xylem fibre is:

Which of the following is a component of phloem?

Damaged sieve tubes are sealed by the deposition of:

Aerenchyma is helpful in plants by

$A$ parenchymatous cell which stores ergastic substances (waste products) is

The first formed primary phloem is referred to as $A$. The later formed primary phloem is referred to as $B$. Choose the correct combination of $A$ and $B$.