Which circuit has three resistors connected in parallel? (pic attached)

Which of the following describes something an engineer would probably do first when developing new technology meant to reduce ocean pollution? o a. evaluate the benefits and challenges of using certain chemicals to purify water. o b. research new scientific findings in regard to ocean cleanup. o c. identify the need to reduce ocean pollution. o d. research what has been done in the past to clean up oceanic oil residue.

Anybody wanna ? (picture included? )

What is the single most important equation in all of physics?