NEET 2019 Model Question Paper 4

Read the following statements (A-D). Identify the option which is correct regarding sickle cell anaemia (SCA)
A) Gene Hbβs provide a classical example of pleiotropy
B) Increasing number of carries of SCA in African population is due to natural selection
C) SCA causes Haemolytic anaemia and it causes increases resistance to malarial parasite.