Which one of the following types of glass can cut off ultraviolet rays?

Crookes glass is the correct choice because it is a specially formulated glass containing cerium oxide mixed with silica; the cerium oxide component strongly absorbs ultraviolet radiation and therefore ‘cuts off’ harmful UV from sunlight. Ordinary clear soda‑lime glass and common borosilicate glasses (e.g., Pyrex or Jena) do not inherently block UV across the short‑wavelength region unless they are specially coloured or treated. For example, amber (brown) glass variants are deliberately formulated (with iron/oxide additives) to absorb ultraviolet wavelengths for light‑sensitive packaging, illustrating that colouration/additives — not the base soda or borosilicate composition alone — provide UV protection. Hence Crookes glass is the standard answer.