Question 461Electricity & Electronics - QMED

The correct answer is B) Autotransformers. Autotransformers use a single winding to produce voltage transformation, unlike step-up, step-down, and isolation transformers which require two separate windings. In an autotransformer, a portion of the winding is used as the primary and the remainder as the secondary, allowing for a more compact and cost-effective design compared to traditional two-winding transformers. The other options are incorrect because step-up, step-down, and isolation transformers all require two separate windings to achieve voltage transformation, rather than utilizing a single winding like an autotransformer.