Which structure keeps adjacent cells in contact with each other?

What is the bridge between two plant cells made of?

Select the correct combination of the statements regarding the characteristics of the middle lamella:
$a$. It holds the different neighbouring cells together.
$b$. It is composed of $Mg$ pectate only.
$c$. It gets dissolved during the ripening of fruits.
Correct statements is/are:

Which structure provides protection to the cell and holds the outer parts of the cell in place?

The organelle labelled by which alphabet is absent in animal cells?

What is the middle lamella in a plant cell composed of?