They were joined by Oklahoma State freshman Cade Cunningham, Illinois junior Ayo Dosunmu, Gonzaga senior Corey Kispert and Arizona State senior Remy Martin. Kispert and Martin tied for the final spot with 26 votes each.
Garza was the lone unanimous choice, receiving all 64 votes from a nationwide media panel that chose the team released Wednesday.
"I couldn't be more excited about this year and coming back,'' Garza said. "Going through the process, I learned a lot, but at the end of the day, going through this team's potential, I felt like this was something I couldn't turn down and not be a part of.''
The 6-foot-11 Garza was an All-American last season and opted to return to the Hawkeyes after testing the NBA waters. He averaged 23.9 points and 9.8 rebounds to finish second to Dayton's Obi Toppin as the AP national player of the year.
Iowa was ranked a program-high No. 5 in the AP preseason Top 25, in large part due to Garza's decision to return.
"He might average a point or two less, but all that kid cares about is winning,'' Iowa coach Fran McCaffrey said. "He's put the time in. He's not rested on his accomplishments. He's hungrier than he's ever been. There's no better example for these young guys than Luka Garza.''
Butler was a third-team All-American last season and, like Garza, withdrew his name from the NBA draft to return for his senior season for the Bears, who are No. 2 in the preseason poll. He was second with 61 votes.
"Jared has shown tremendous growth in his first two seasons at Baylor, both on and off the court,'' Baylor coach Scott Drew said. "He has always been a great teammate with an infectious personality and now that he's an upperclassman, he's taken on more of a leadership role.''
The dynamic Dosunmu also took a look at the NBA before deciding to return, a huge boost for the No. 8 Illini.
The 6-5 guard was the first Illinois player in 20 years to lead the team in scoring as a freshman and sophomore. Dosunmu can do a little of everything on the court, averaging 16.6 points, 4.3 rebounds and 3.3 assists while shooting 48% from the floor last season.
Cunningham arrived in Stillwater with plenty of hype as the highest-rated recruit in school history. The 6-8 guard can play the point or fill it up when he wants to, putting him at the top of numerous NBA draft boards for 2021.
Gonzaga was the AP preseason No. 1 for the first time and Kispert's decision to return was a big part of it.
The 6-7 senior is a superb 3-point shooter (44% last season) and a good slasher to the basket. He averaged 13.9 points and 4.0 rebounds on a deep team last season and will be a key cog on a team with Final Four aspirations.
Martin started his career at Arizona State has the bouncy-haired energizer off the bench, lifting his team with pizzazz and hard-nosed defense. The 6-foot guard has since developed into an unquestioned leader on a team loaded with talented guards.
Martin averaged 19.1 points, 4.1 rebounds and 3.1 assists last season and his decision to bypass the NBA to stay for his senior season has expectations running high for the 18th-ranked Sun Devils.