What does the part labeled $''A''$ in the given figure represent?

The main structural component of a virus is...

Lichen is usually cited as an example of 'symbiosis' in plants where an algal and a fungal species live together for their mutual benefit. Which of the following will happen if algal and fungal partners are separated from each other?
$A$. Both will survive and grow normally and independent from each other.
$B$. Both will die.
$C$. Algal component will survive while the fungal component will die.
$D$. Fungal component will survive while algal partner will die.
Based on your answer,how do you justify this association as symbiosis?

It is responsible for potato spindle tuber disease.

Identify the odd one out in the context of living organisms.

Identify the parts labelled as $A, B, C$ and $D$ in the given diagram of a bacteriophage.