UC Davis - College of Engineering v.s. College of Biological Sciences

I’d just like to know which one has tougher admissions.

On my UC application for UC Davis, I had put my “engineering” major as my primary major and my “biological science” major as my alternate, thinking the College of Biological Sciences had more lenient admissions.

I’d just like some clarification, thanks.

For UC Davis:
College of Biological Sciences admit by college, so not dependent upon major

College of Engineering admits by academic department, so dependent upon major

Most admitted students are accepted to their first-choice major, but alternate majors may be considered.