Why are the members of Rhodophyceae commonly called red algae?

Why are members of Rhodophyceae called red algae?

In respect of classification of algae, the members of Phaeophyceae are commonly called :

Assertion :- Members of Rhodophyceae are called red algae Reason :- Red algae posses, predominance of r- phycocrythrin in their body.

Assertion :- Members of Rhodophyceae are called red algae Reason :- Red algae posses, predominance of r- phycoerythrin in their body.

Assertion :- Members of Rhodophyceae are called red algae Reason :- Red algae posses, predominance of r- phycoerythrin in their body.

The members of class Holothuroidea are commonly called as