The drawbacks of ‘Armature Resistance Control’ method of speed control of a dc motor are1. A large amount of power is lost in the external resistance R2. This method gives the speed below normal values3. For a specified value of R, speed reduction is not constant. It varies with motor loadWhich of the above statements are correct?

• A. 1, 2 and 3
• B. 1 and 2 only
• C. 1 and 3 only
• D. 2 and 3 only