Which among the following statements are correct :

(A) Continued cross -pollination result in inbreeding depression.

(B) In case of castor and maize , it prevent autogamy but not geitonogamy.

(C) In papaya, it prevents  geitonogamy but not autogamy .

(D)  The pistils has the ability to recognise the pollen, whether it is of the right type (compatible) or of the wrong type (incompatible).

B and D only 

The correct answer is Option (2)- B and D only

Statement A (Continued cross-pollination results in inbreeding depression): Incorrect. Inbreeding depression is usually caused by self-pollination or mating between closely related individuals, not by cross-pollination. Cross-pollination typically promotes genetic diversity.

Statement B (In case of castor and maize, it prevents autogamy but not geitonogamy): Correct.

Castor and maize are unisexual flowers that has separate sex organs and are present in two different flowers in the same plant. Autogamy which is self-pollination can be prevented as male and female flowers are separate but allows geitonogamy (pollination between different flowers on the same plant).

Statement C (In papaya, it prevents geitonogamy but not autogamy): Incorrect. In papaya, being a dioecious plant, both autogamy (self-pollination) and geitonogamy (pollination between flowers of the same plant) are prevented because male and female flowers are on separate plants.

Statement D (The pistil has the ability to recognize the pollen, whether it is of the right type or of the wrong type): Correct. Pollen of the right type and wrong type, either from other species or from the same plant also land on the stigma. The pistil has the ability to recognise the pollen, whether it is of the right type (compatible) or of the wrong type (incompatible). If it is of the right type, the pistil accepts the pollen and promotes post-pollination events.

Therefore, the correct option is B and D only.