Which one of the following statements concerning the algae is wrong?

Which pigment is present in all algae?

Carrageenin,a jelly-like substance,is obtained from:

Which of the following statements are applicable to brown algae?
$(I)$ They contain pigments like chlorophyll $a$,chlorophyll $c$,carotenoids,and xanthophylls.
$(II)$ They vary in color from olive green to various shades of brown.
$(III)$ Food is stored as complex carbohydrates,in the form of laminarin or mannitol.
$(IV)$ The cell wall is composed of cellulose and algin.
$(V)$ The cell wall is covered on the outside by a gelatinous coating of algin.

Mannitol is the stored food in

In algae,asexual reproduction occurs by the production of different types of spores. The most common type of spore is