Question

$\text{Assertion (A):}$ Lower invertebrates like sponges and coelenterates exchange $O_2$ with $C{O}_2$ by simple diffusion over their entire body surface.
$\text{Reason (R):}$ Respiratory organs are absent in these lower animals as they do not have connective tissue like blood to transport gases.
In the light of above statements, select the correct option.

• A. (A) is true and (R) is false
• B. (A) is false and (R) is true
• C. Both (A) & (R) are true but (R) is not the correct explanation of (A)
• D. Both (A) & (R) are true and (R) is the correct explanation of (A)

Answer 1

The correct option is D Both (A) & (R) are true and (R) is the correct explanation of (A)

Answer (1)
In lower invertebrates, no well-developed respiratory organ is present. Exchange of gases occurs by simple diffusion.