Viruses multiply

Which infectious agents are smaller than viruses?

Which of the following is smaller than a virus?

Which of the following is an example of an animal virus?

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?

Which of the following microbes is made up of protein only?