Algae are 71. ______ and known as aquatic plant. In Latin, it means seaweed but not all of them are weed or lives in the sea. Some 72.______ can be found in soil, snow or in animal species and 73. slim quite a long time without water. The world’s scientists agree that algae have four categories which are distinguished by 74. ________. However, one type is still 75. _______.
a. uncertain
b. varieties
c. slim
d. pigmentations
e. live