Questions

The relationship between two organisms such that one lives on the other and one gets benefited while the other get infected.

A man with colour blindness will see red and green as same. 

It is due to the deficiency of Vitamin A. Retinol which is present in vitamin A. Its deficiency causes night blindness. It is available in carrots. 

A bus is a group of conducting lines that carriers data, address, & control signals.

A bus is two or many wire communication method. A bus which communicate between two active devices, it may transfer address, data etc..