Answer:
(a) decrease
Step-by-step explanation:
Viscosity is the resistance which occur to flow of the fluid.
More the inter molecular forces between particles of the liquid, more the viscosity of liquid.
Effect of temperature on viscosity:-
Viscosity decreases with the increase in the temperature as forces among the particles decrease on increasing temperature. The kinetic energy of the particles of the liquid increases causing to move in more random motions and thus weaker inter molecular forces and this offer less resistance to the flow.
Hence, viscosity of the liquids decrease with the increasing temperature.