Why does current increase when internal resistance decreases?

[krypt0nite]

Diagram
The answer is A and i don't really understand why that is so. I am thinking that since Emf - Ir= Vterminal. The current must go up but i am not sure exactly why is that happening. I've read through my handbook but can't seem to find anything on this type of problem.

 

[nishant]

see when the resistance is added in parallel to the 4{}| the the equvalent resistance goes down due to which the current increases and voltage across the 5{} is given by
I*R,THEREFORE THE VOLTAGE ACROSS IT ALSO INCREASES.

 

[nishant]

terminal voltage is the voltage across the battery when it is connected in a circuit,as the current increases the terminal voltage which is equal to=E-IR decreases,here the R stands for internal resistance of the battery