a 20 A fuse is connected in series with a circuit containing a 240 V source. What is the minimum resistance required to prevent the fuse from melting

Texture and composition are different because they are not the same aspect. texture has to do with feel and so on, where as composition is the chemical makeup which you cant touch like you can texture.

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current