Question

question 44
animals that lack a backbone are referred to as:
a fish
b cartilaginous
c monotremes
d invertebrates
e marsupials

Explanation:

To solve this, we analyze each option:

• Option A: Fish are vertebrates (have a backbone). Eliminate.
• Option B: Cartilaginous refers to a type of skeleton (e.g., sharks), but these are still vertebrates. Eliminate.
• Option C: Monotremes are a type of mammal (vertebrate). Eliminate.
• Option D: Invertebrates are defined as animals without a backbone. This matches the description.
• Option E: Marsupials are mammals (vertebrate). Eliminate.

Answer:

D. Invertebrates