Assertion : Plane and convex mirrors can produce real images of objects.
Reason : A plane or convex mirror can produce a real image, if the object is virtual.

Choose the correct one out of the given responses.

Q. Assertion: Focal length of a convex mirror is $20\text{cm}$. If a real object is placed at a distance of $20\text{cm}$ from the mirror, its virtual, erect and diminished image will be formed.
Reason: If a virtual object is placed at $20\text{cm}$ distance behind the convex mirror, its image is formed at infinity.
Choose the correct option based on it.

Q. Assertion- pH of the stomach is more than 7.
Reason- Stomach contains oxyntic cells that produce HCl.

Q. Assertion: 3 + 7 = 9 is a statement.
Reason: A sentence that can be judged to be true or false, but not both, is called a statement.
(a) Both Assertion and Reason are true and Reason is a correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not a correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.

Q. (i)
Assertion: A circle is not a rectilinear figure.
Reason: A figure formed by straight lines only is called a rectilinear figure.
(a) Both Assertion and Reason are true and Reason is a correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not a correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.
(ii)
Assertion: All right angles are equal to one another.
Reason: A unique line passes through a single point.
(a) Both Assertion and Reason are true and Reason is a correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not a correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.

Q. Regarding the assertion and reason, choose the correct option.
Assertion [A]: Deforestation is one main factor contributing to global warming.
Reason [R]: Besides, $C{O}_2$, methane and CFCs are also greenhouse gases.