Those are literally the minimum possible requirements to get a diploma anywhere in the State of California; judging from the document, school districts may impose stricter requirements.

Those are unusually lenient from what I've seen; my home school district [not in California] currently requires 4 years of English, 3 years each of math, science, and social studies, 2 each of PE and foreign language or fine arts, 1 year of economics/personal finance, and 4 electives. And apparently 1 course must be AP, IB or honors. As a matter of practice, you'd be expected to take 4 years of English, math, science, and social studies, and at least 3 of foreign language anyways (and indeed, there's an 'advanced degree' that has those requirements; it looks like 2/3 of students graduated with the 'advanced degree').