Blood

To determine the possible blood groups of a child when one parent has blood group ‘A’ and the other has blood group ‘O’, we must consider the genetics of blood groups. Blood type is determined by the alleles inherited from the parents. Blood group ‘A’ can be either genotype AA or AO, while blood group ‘O’ can only be OO.

Here's a breakdown of the possible scenarios:

• If the parent with blood group ‘A’ has genotype AA, the potential combinations with an ‘O’ type parent (genotype OO) could be AO (blood type ‘A’).
• If the parent with blood group ‘A’ has genotype AO, the potential combinations are either AO (blood type ‘A’) or OO (blood type ‘O’).

Therefore, the child can potentially inherit either blood group ‘A’ or ‘O’, depending on the genetic combination. Hence, the correct answer is:

Either ‘A’ or ‘O’

To identify the incorrect statements from the given options, let's evaluate each one:

(A) Gametocytes of Plasmodium develop in the RBCs: This statement is correct. Gametocytes are the sexual forms of the Plasmodium parasite that develop in red blood cells (RBCs) before being taken up by mosquitoes.

(B) Ascariasis pathogens are transmitted to a healthy person through the bite by female mosquito vectors: This statement is incorrect. Ascaris lumbricoides, the parasitic worm causing Ascariasis, is transmitted through ingestion of contaminated food or water, not through mosquito bites.

(C) Entamoeba histolytica is a helminth parasite in the small intestine of humans, causing amoebiasis: This statement is incorrect. Entamoeba histolytica is not a helminth; it is a protozoan parasite that causes amoebiasis in the intestines.

(D) Malarial parasite reproduces asexually in the gut of the mosquito: This statement is incorrect. The Plasmodium (malaria parasite) reproduces sexually in the gut of the mosquito. Asexual reproduction occurs in the human host.

(E) Filarial worms reside in the lymphatic vessels of the lower limbs: This statement is correct. Filarial worms such as Wuchereria bancrofti commonly reside in the lymphatic system, causing conditions such as lymphatic filariasis.

Thus, the incorrect statements are (B), (C), and (D). Therefore, the correct option is: (B), (C) and (D) only