Match column-I with column-II and choose the correct option.

Column-I	Column-II
A. Agar	I. Single cell protein, used as food supplements by space travellers
B. Algin	II. Red algae
C. Carrageen	III. Brown algae
D. Chlorella	IV. Gelidium, Gracilaria Spirullina

Agar is a gelatinous substance obtained from certain red seaweeds and used in biological culture media and as a thickener in foods. Eg, Gelidium and Gracilaria. Alginic acid, also called algin or alginate, is an anionic polysaccharide distributed widely in the cell walls of brown algae, where through binding with water it forms a viscous gum. Carrageen is a colloid extracted from various red algae (as Irish moss) and used especially as a stabilizing or thickening agent. Chlorella and Spirullina are unicellular algae, rich in proteins and are used as food supplements by space travellers.