The MultiSIM BLUE doesn’t have resistive sensors, but you can simulate them using common potentiometers. You only have to choose a potentiometer with the same value of the sensor in the condition of maximum resistance.
Placing this pot4entiometer in the circuit you can use the correspondent key to vary the resistance simulating the action of the sensor.
For instance, a 470 k ohm or 1 M ohm can replace an LDR in a simulation.