Question

Assertion (A): Angina pectoris occurs due to transient myocardial ischemia without causing permanent damage to heart muscles. Reason (R): In coronary artery disease, narrowing of coronary arteries reduces blood supply to myocardium.

• A. Both (A) and (R) are true. (R) is correct explanation for (A)
• B. Both (A) and (R) are true. (R) is not correct explanation for (A)
• C. (A) is true. But (R) is false
• D. (A) is false. But (R) is true

Hint:

Angina = Temporary chest pain due to reduced oxygen supply.

Answer 1

The Correct Option is A

Step 1: Read both statements.
Assertion: Angina pectoris is short lived heart muscle starvation (ischemia) that does not leave permanent damage. Reason: In coronary artery disease the coronary arteries become narrow and less blood reaches the heart muscle.

Step 2: Check the Assertion.
Angina is a chest pain that comes when the heart muscle does not get enough oxygen for a short while. Because it is temporary, the muscle cells survive, so there is no lasting damage. The Assertion is true.

Step 3: Check the Reason.
The coronary arteries feed the heart muscle. In coronary artery disease they get narrowed, often by fatty deposits, so blood flow drops. The Reason is true.

Step 4: Does the Reason explain the Assertion?
Yes. The narrowing cuts the blood supply, and that reduced supply is exactly what causes the brief oxygen shortage we call angina. So the Reason is the direct cause behind the Assertion.

Step 5: Match with the options.
Both statements are true and the Reason correctly explains the Assertion.

Step 6: Conclusion.
Therefore the correct answer is "Both (A) and (R) are true. (R) is correct explanation for (A)". \[ \boxed{\text{Both true, R explains A}} \]