Answer: The museum was visited by them yesterday.
Step-by-step explanation:
Active voice is written the subject then the verb then the object.
(Subject- They)
(Verb-visited)
(Object-that museum)
{They visited that museum yesterday}active{
Passive voice is written as an object then a verb then a subject.
(Object-that museum)
(Verb-visited)
(Subject-them)
{The museum was visited by them yesterday.}passive{