Question

If '+' sign is assigned to beneficial interaction, '–' sign to detrimental and '0' sign to neutral interaction, then the population interaction represented by '+' '–' refers to

• A. parasitism
• B. mutualism
• C. amensalism
• D. commensalism

Answer 1

The correct option is A parasitism

Parasitism is a relationship between two living organisms of different species in which one organism, i.e. parasite obtains its food directly from the host. In this relationship the parasite is benefitted (+) and the host is harmed (-). So, this type of population interaction is represented by '+' '-'.
Parasitism + , –
Mutualism + , +
Amensalism 0, –
Commensalism +, 0