Producers must understand the marginal benefit of making an additional unit which shows the possible gain. Marginal benefit is used in business and economics as a measurement of the change in benefits over the change in quantity. Possible gain is one example of benefit. This measurement provides the relevant measurement of benefits at a specific level of production and consumption.
I think it's D because it's made out of facts. The other ones are more likely to include bias.
Observing, Looking, Collecting, there are a few words for "gathering information with your eyes".
design of the network
security for the network
documentation
identifying and fixing issues
