The correct option is B concave
Since the object and the image lie on the same side of the principal axis, the image is formed by real intersection of the reflected rays. Also the image is fomed below the principal axis hence image I real and inverted w.r.t object O.
Also, As O and I are on either side of the principal axis, I will be inverted image of the object.
Hence, the mirror is concave .
Also, Real images are formed by only concave mirrors.
∴Option (b) is correct.