The correct option is B atopy
Atopy refers to the inherent tendency towards allergies. Environmental allergens(for the individual) usually enter through the intact mucosal surface. It is mostly due to multiple gene inheritance. In this case, the body produces exaggerated amount of IgE in response to the proteinaceous allergens.
Atrophy is a general term used to refer to decrease in size/ wastage/degeneration of mature tissues like muscle, neural tissues, etc.
Abcess is a condition that involves pain and collection of pus caused due to infections. Abcesses may be external as well as internal in nature.
Anaemia refers to the condition in which the RBC number becomes less thereby haemoglobin levels become lower than normal. It may be caused due to a number of reasons such as blood loss, genetic conditions, deficiencies of vitamins, folic acid, iron, etc.