Parasitism is a symbiotic relationship where one organism benefits while harming the other. one organism benefits while the other has no benefit nor is it harmed. both organisms benefit.

## Step 1<br />The problem is asking us to identify the correct definition of parasitism among the given options. Parasitism is a type of symbiotic relationship between two organisms, where one organism, known as the parasite, benefits at the expense of the other, known as the host.<br />## Step 2<br />The parasite benefits by deriving nutrients at the host's expense, often causing harm to the host. This is different from other types of symbiotic relationships such as mutualism, where both organisms benefit, and commensalism, where one organism benefits while the other is neither helped nor harmed.<br />## Step 3<br />Based on the above information, the correct definition of parasitism is that one organism benefits while harming the other.