Fair Oaks Farms, one of the largest dairy farms in the country, is rapidly becoming a zero-carbon-footprint dairy. Starting with the 430,000 gallons of manure produced daily, a number of innovations designed to capture value from the manure and assorted by-products are leading to greater efficiencies and at the same time are environment-friendly. This is an example of a firm defining its ________ envelope.
a) environmental
b) internal
c) financial
d) strategic