Question about L&S Final Assignment

When it says list prerequisite courses for each major, is it referring to the course number (Math 1A) or the course title (Methods of Mathematics: Calculus, Statistics, and Combinatorics Calculus)?

Not sure what “L&S Final Assignment” you are referring to, but they probably mean the course number rather than the title, since different courses could have the same or similar titles.

Also, MATH 1A is “Calculus”, while MATH 10A is “Methods of Mathematics: Calculus, Statistics, and Combinatorics”. Note that MATH 1B and 10B have the same titles respectively.
http://guide.berkeley.edu/courses/math/