Which alga is used by space travellers as a food supplement?

Read the following statements and choose the set of correct statements: In the members of Phaeophyceae,
$A$. Asexual reproduction occurs usually by biflagellate zoospores.
$B$. Sexual reproduction is by oogamous method only.
$C$. Stored food is in the form of carbohydrates which is either mannitol or laminarin.
$D$. The major pigments found are chlorophyll $a$,$c$ and carotenoids and xanthophyll.
$E$. Vegetative cells have a cellulosic wall,usually covered on the outside by gelatinous coating of algin.
Choose the correct answer from the options given below:

In which members of algae is the formation of zoospores not observed?

The product of conjugation in $Spirogyra$ or fertilization in $Chlamydomonas$ is .....

Algae include unicellular forms like $A$,filamentous forms like $B$,and colonial forms like $C$. Here $A, B$,and $C$ refer to:

Which of the following shows the absence of chlorophyll $b$?