Final answer:
The correct answer is that all building sewer and sewer piping trench deeper than the building's footing and installed parallel to it should be installed at least 90 degrees from the footing. This ensures the structural integrity of the building's foundation is not compromised.
Step-by-step explanation:
The question pertains to the installation of building sewer and sewer piping with relation to a building's footing. When installing sewer piping that is deeper than the footing of any building or structure and is meant to be installed parallel with the footing, it is essential to maintain a certain distance or orientation from the footing to avoid structural and serviceability issues.
The correct answer to the student's question is: d. 90 degrees from the footing. Sewer pipes should not run parallel right next to the footing but rather at a safe distance away to prevent any potential damage to the building's foundation. Typically, codes and standards specify this to ensure that there is no undermining of the structural integrity of footings and to provide enough space for maintenance or repairs without affecting the building.