Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).
Assertion (A): Ligamentum arteriosum joins pulmonary trunk and aortic arch.
Reason (R): It is the remnant of fossa ovalis.
In light of the above statements, choose the correct answer from the options given below.

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

Hint:

Ligamentum arteriosum is the remnant of the foetal ductus arteriosus.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
In the foetus the ductus arteriosus joins the pulmonary trunk to the aortic arch, bypassing the lungs.

Step 2: Check the Assertion
After birth it closes into the ligamentum arteriosum, which still connects the two, so (A) is true.

Step 3: Check the Reason
Fossa ovalis is a depression left by the closed foramen ovale in the interatrial septum, so (R) is false.

Final Answer:
(A) is true but (R) is false. \[ \boxed{\text{(C) }\text{(A) is true but (R) is false.}} \]