Question

Which among the following is not a unicellular organism?

• A. Paramoecium
• B. Amoeba
• C. Humans
• D. Bacteria

Answer 1

The correct option is (B):

Explanation of the correct option:

1. ​The organisms that possess multiple cells together performing specific functions are called multicellular functions.
   
2. Humans are multicellular organisms containing multiple cells with different functions.
   
3. Humans possess an organ system level of organization.
   

Explanation of the incorrect options:

Option (A):

1. Amoeba is one of the unicellular eukaryotes as the entire organism is made up of a single cell. ​

Option (C):

1. Paramoecium is another unicellular eukaryote. ​

Option (D):

1. ​Bacteria is commonly a unicellular prokaryotic organism.
   

Final Answer: Humans are not unicellular organisms.