Choose the word which is different from the rest.

Cot
Sheet
Quilt
Pillow E. Blanket

The answer is cot.

A cot is a small bed, typically one that can be folded up for easy storage. Sheets, quilts, pillows, and blankets are all items that are used on beds.

Sheets are flat pieces of fabric that are used to cover mattresses. Quilts are thick, padded blankets that are often made with a patchwork design. Pillows are soft, cushioned objects that are used to support the head and neck while sleeping. Blankets are soft, lightweight coverings that are used to keep people warm.

Cot is the only item in the list that is not used on a bed.