Remember that complementary angles add to 90 degrees.
so therefor, you can find the complement of m<A by solving
90 - 77 = A
A = 13 degrees
^^^ This explains the second part.
The compliment of a compliment can be found by subtracting the known compliment from 90 :)
The one you have highlighted is correct
It represents the y axis and the x axis. hope this helps! :)