The question asks us to identify which element does not exhibit allotropic modification. Allotropic modification refers to the ability of an element to exist in different forms or structures with different physical properties.

Option 1: Iodine

Iodine is an element that exhibits allotropic modification. It can exist in two main forms: violet crystalline solid and brownish amorphous solid. Therefore, option 1 is not the correct answer.

Option 2: Sulphur

Sulphur is an element that exhibits allotropic modification. It can exist in multiple forms, such as rhombic sulphur (yellow crystals), monoclinic sulphur (plastic form), and amorphous sulphur (powder form). Therefore, option 2 is not the correct answer.

Option 3: Phosphorus

Phosphorus is an element that exhibits allotropic modification. It can exist in several different forms, including white phosphorus, red phosphorus, and black phosphorus. Therefore, option 3 is not the correct answer.

Option 4: Carbon

Carbon is an element that exhibits allotropic modification. It can exist in multiple forms, such as diamond, graphite, amorphous carbon, and fullerenes. Therefore, option